NCERT MCQ ON Trial Balance and Rectification of Errors:
Question 1. Agreement of trial balance is affected by (a) one sided errors only (b) two sided errors only (c) both (a) and (b) (d) none of the above
Answer: (c) both (a) and (b).
Question 2. Which of the following is not an error of principle? (a) Purchase of furniture debited to purchases account. (b) Repairs on the overhauling of second hand machinery purchased debited to repairs account. (c) Cash received from Manoj posted to Saroj. (d) Sale of old car credited to sales account.Answer
Answer: (c) Cash received from Manoj posted to Saroj.
Question 3. Which of the following is not an error of commission? (a) Overcasting of sales book. (b) Credit sales to Ramesh Rs. 5,000 credited to his account. (c) Wrong balancing of machinery account. (d) Cash sales not recorded in cash book.Answer
Answer: (d) Cash sales not recorded in cash book.
Question 4. Which of the following errors will be rectified through suspense account? (a) Sales return book undercast by Rs. 1,000. (b) Sales return by Madhu Rs. 1,000 not recorded. (c) Sales return by Madhu Rs. 1,000 recorded as Rs. 100. (d) Sales return by Madhu Rs. 1,000 recorded through purchases return bookAnswer
Answer: (a) Sales return book undercast by Rs. 1,000.
Question 5. If the trial balance agrees, it implies that: (a) there is no error in the books. (b) there may be two sided errors in the book. (c) there may be one sided error in the books. (d) there may be both two sided and one sided errors in the books.Answer
Answer: (b) there may be two sided error in the books.
Question 6. If suspense account does not balance off even after rectification of errors it implies that: (a) there are some one sided errors only in the books yet to be located. (b) there are no more errors yet to be located. (c) there are some two sided errors only yet to be located. (d) there may be both one sided errors and two sided errors yet to be located.Answer
Answer: (a) there are some one sided errors only in the books yet to be located.
Question 7. If wages paid for installation of new machinery is debited to wages account, it is (a) an error or commission. (b) an error of principle (c) a compensating error. (d) an error of omission.Answer
Answer: (b) an error of principle.
Question 8. Trial balance is: (a) an account. (b) a statement. (c) a subsidiary book. (d) a principal book.Answer
Answer: (b) a statement.
Question 9. A trial balance is prepared: (a) after preparation financial statement. (b) after recording transactions in subsidiary books. (c) after posting to ledger is complete. (d) after posting to ledger is complete and accounts have been balanced.Answer
Answer: (d) after posting to ledger is complete and accounts have been balanced
Fill in the blanks
Question 1. An item is posted to the wrong side of an account. The error will be of …………….. the amount.Answer
Answer: double
Question 2. Errors of principle ………………… affect the Trial Balance.Answer
Answer: do not
Question 3. If an accounting error has increased the profit, for correction, profit and loss account, will be ……………..Answer
Answer: debited
Question 4. A Trial Balance ……………….. despite the existence of several errors in the books.Answer
Answer: tallies
Question 5. Undercasting in wages account is rectified by ………………. suspense account and wages account.Answer
Answer: crediting, debiting
Question 6. Overcasting in salaries account is rectified by ………………. suspense account and ……………… salaries account.Answer
Answer: debiting, crediting
Question 7. If the Trial Balance does not ……………… it indicates that some ……………….. have been committed.Answer
Answer: tally, errors
Question 8. Journal entries passed to correct errors are called ……………..Answer
Answer: rectifying entries
Question 9. The last step of preparing Trial Balance is to ascertain the ……………….. of its two amount columns.Answer
Answer: sum
Question 10. While preparing ………………… the ledger account balances are carried from the Trial Balance.Answer
Question 1. A bank reconciliation statement is prepared by (a) Creditors (b) Bank (c) Account holder in a bank (d) DebtorsAnswer
Answer: (c) Account holder in a bank
Question 2. A bank reconciliation statement is prepared with the balance (a) Passbook (b) Cash book (c) Both passbook and cash book (d) None of theseAnswer
Answer: (c) Both passbook and cash book
Question 3. Passbook is a copy of: (a) Customer account (b) Bank column of cash book (c) Cash column of cash book (d) Receipts and paymentsAnswer
Answer: (a) Customer account
Question 4. Unfavourable bank balance means (a) Credit balance in passbook (b) Credit balance in cash book (c) Debit balance in cash book (d) None of theseAnswer
Answer: (b) Credit balance in cash book
Question 5. Favourable bank balance means : (a) Credit balance in the cash book (b) Credit balance in passbook (c) Debit balance in the cash book (d) Both (b) and (c)Answer
Answer: (d) Both (b) and (c)
Question 6. A bank reconciliation statement is mainly prepared for (a) Reconcile the cash balance of the cash book (b) Reconcile the difference between the bank balance shown by the cash book and bank passbook (c) Both (a) and (b) (d) None of theseAnswer
Answer: (b) Reconcile the difference between the bank balance shown by the cash book and bank passbook
Fill in the blanks
Question 1. Passbook is a copy of ………………. as it appears in the ledger of the bank.Answer
Answer: customer account
Question 2. When money is withdrawn from the bank, the bank ……………… the account of the customer.Answer
Answer: debit
Question 3. Normally, the cash book shows a debit balance, passbook shows ……………….. balance.Answer
Answer: credit
Question 4. Favourable balance as per the cash book means …………….. balance in the bank column of the cash book.Answer
Answer: debit
Question 5. If the cash book balance is taken as starting point the items which make the cash book balance smaller than the passbook must be ………………. for the purpose of reconciliation.Answer
Answer: added
Question 6. If the passbook shows a favourable balance and if it is taken as the starting point for the purpose of bank reconciliation statement then cheques issued but not presented-for payment should be ……………… to find out cash balance.Answer
Answer: deducted
Question 7. When the cheques are not presented for payment, favourable balance as per the cash book is ……………… than that of the passbook.Answer
Answer: lower/less
Question 8. When a banker collects the bills and credits the account passbook overdraft shows ……………….. balance.Answer
Answer: less/lower
Question 9. If the overdraft as per the passbook is taken as the starting point, the cheques issued but not presented are to be ………………… in the bank reconciliation statement.Answer
Answer: added
Question 10. When the passbook balance is taken as the starting point items which makes the passbook balance ……………… than the balance in the cash book must be deducted for the purpose of reconciliation.Answer
Answer: higher
State whether each of the following statements is True or False.
Question 1. Passbook is the statement of account of the customer maintained by the bank.Answer
Answer: True
Question 2. A business firm periodically prepares a bank reconciliation statement to reconcile the bank balance as per the cash book with the passbook as these two show different balances for various reasons.Answer
Answer: True
Question 3. Cheques issued but not presented for payment will reduce the balance as per the passbook.Answer
Answer: False
Question 4. Cheques deposited but not collected will result in increasing the balance of the cash book when compared to passbook.Answer
Answer: True
Question 5. Overdraft as per the passbook is less than the overdraft as per cash book when there are cheques deposited but not collected by the banker.Answer
Answer: False
Question 6. The debit balance of the bank account as per the cash book should be equal to the credit balance of the account of the business in the books of the bank.Answer
Answer: True
Question 7. Favourable bank balance as per the cash book will be less than the bank passbook balance when there are unpresented cheques for payment.Answer
Answer: True
Question 8. Direct collections received by the bank on behalf of the customers would increase the balance as per the bank passbook when compared to the balance as per the cash book.Answer
Answer: True
Question 9. When payments made by the bank as per the standing instructions of the customer, the balance in the passbook will be more when compared to the cash book.Answer
Q1.When a firm maintains a cash book, it need not maintain (a) Journal Proper (b) Purchases (journal) book (c) Sales (journal) book (d) Bank and cash account in the ledger
Answer: (d) Bank and cash account in the ledger
Q2.Double column cash book records (a) All transactions (b) Cash and bank transactions (c) Only cash transactions (d) Only credit transactionsAnswer
Answer: (b) Cash and bank transactions
Q3.Goods purchased on cash are recorded in the (a) Purchases (journal) book (b) Sales (journal) book (c) Cash book (d) Purchases return (journal) bookAnswer
Answer: (c) Cash book
Q4.Cash book does not record transaction of: (a) Cash nature (b) Credit nature (c) Cash and credit nature (d) None of theseAnswer
Answer: (b) Credit nature
Q5.Total of these transactions is posted in purchase account: (a) Purchase of furniture (b) Cash and credit purchase (c) Purchases return (d) Purchase of stationeryAnswer
Answer: (b) Cash and credit purchase
Q6.The periodic total of sales return journal is posted to : (a) Sales account (b) Goods account (c) Purchases return account (d) Sales return accountAnswer
Answer: (d) Sales return account
Q7.Credit balance of bank account in cash book shows : (a) Overdraft (b) Cash deposited in our bank (c) Cash withdrawn from bank (d) None of theseAnswer
Answer: (a) Overdraft
Q8.The periodic total of purchases return journal is posted to : (a) Purchase account (b) Profit and loss account (c) Purchase returns account (d) Furniture accountAnswer
Answer: (c) Purchase returns account
Q9.Balancing of account means (a) Total of debit side (b) Total of credit side (c) Difference in total of debit & credit (d) None of theseAnswer
Answer: (c) Difference in total of debit & credit
Fill in the Correct Words
Question 1. Cash book is a …………….. journal.Answer
Answer: Subsidiary
Question 2. In Journal proper, only ………………. discount is recorded.Answer
Answer: Cash
Question 3. Return of goods purchased on credit to the suppliers will be entered in ………………. Journal.Answer
Answer: Purchases Return
Question 4. Assets sold on credit are entered in ……………….Answer
Answer: Journal Proper
Question 5. Double column cash book records transaction relating to ……………. and ……………….Answer
Answer: Cash, Bank
Q1.When a firm maintains a cash book, it need not maintain (a) Journal Proper (b) Purchases (journal) book (c) Sales (journal) book (d) Bank and cash account in the ledger
Answer: (d) Bank and cash account in the ledger
Q2.Double column cash book records (a) All transactions (b) Cash and bank transactions (c) Only cash transactions (d) Only credit transactionsAnswer
Answer: (b) Cash and bank transactions
Q3.Goods purchased on cash are recorded in the (a) Purchases (journal) book (b) Sales (journal) book (c) Cash book (d) Purchases return (journal) bookAnswer
Answer: (c) Cash book
Q4.Cash book does not record transaction of: (a) Cash nature (b) Credit nature (c) Cash and credit nature (d) None of theseAnswer
Answer: (b) Credit nature
Q5.Total of these transactions is posted in purchase account: (a) Purchase of furniture (b) Cash and credit purchase (c) Purchases return (d) Purchase of stationeryAnswer
Answer: (b) Cash and credit purchase
Q6.The periodic total of sales return journal is posted to : (a) Sales account (b) Goods account (c) Purchases return account (d) Sales return accountAnswer
Answer: (d) Sales return account
Q7.Credit balance of bank account in cash book shows : (a) Overdraft (b) Cash deposited in our bank (c) Cash withdrawn from bank (d) None of theseAnswer
Answer: (a) Overdraft
Q8.The periodic total of purchases return journal is posted to : (a) Purchase account (b) Profit and loss account (c) Purchase returns account (d) Furniture accountAnswer
Answer: (c) Purchase returns account
Q9.Balancing of account means (a) Total of debit side (b) Total of credit side (c) Difference in total of debit & credit (d) None of theseAnswer
Answer: (c) Difference in total of debit & credit
Fill in the Correct Words
Question 1. Cash book is a …………….. journal.Answer
Answer: Subsidiary
Question 2. In Journal proper, only ………………. discount is recorded.Answer
Answer: Cash
Question 3. Return of goods purchased on credit to the suppliers will be entered in ………………. Journal.Answer
Answer: Purchases Return
Question 4. Assets sold on credit are entered in ……………….Answer
Answer: Journal Proper
Question 5. Double column cash book records transaction relating to ……………. and ……………….Answer
Answer: Cash, Bank
Question 6. Total of the debit side of cash book is ……………….. than the credit side.Answer
Answer: More
Question 7. Cash book does not record the ………………. transactions.Answer
Answer: Credit
Question 8. In double column cash book ……………….. transactions are also recorded.Answer
Answer: Bank
Question 9. Credit balance shown by a bank column in cash book is …………………Answer
Answer: Overdraft
Question 10. The amount paid to the petty cashier at the beginning of a period is known as ………………. amount.Answer
Answer: Imprest
Question 11. In purchase book goods purchased on ………………. are recorded.Answer
Answer: Credit
State whether the following statements are True or False
Question 1. Journal is a book of secondary entry.Answer
Answer: False
Question 2. One debit account and more than one credit account in a entry is called compound entry.Answer
Answer: True
Question 3. Assets sold, on credit are entered in sales journal.Answer
Answer: False
Question 4. Cash and credit purchases are entered in purchase journal.Answer
Answer: False
Question 5. Cash sales are entered in sales journal.Answer
Answer: False
Question 6. Cash book records transactions relating to receipts and payments.Answer
Answer: True
Question 7. Ledger is a subsidiary book.Answer
Answer: True
Question 8. Petty cash book is a book having record of big payments.Answer
Answer: False
Question 9. Cash received is entered on the debit side of cash book.Answer
Answer: True
Question 10. Transaction recorded both on debit and credit side of cash book is known as contra entry.Answer
Answer: True
Question 11. Balancing of account means total of debit and credit side.Answer
Answer: False
Question 12. Credit purchase of machine is entered in purchase journal.Answer
Q1.How is weather forecasting useful for different groups? Answer: Weather forecasting is very important for all groups:
Weather forecasts help in taking safety measures in advance in case of the likelihood of bad weather.
It reduces the likely loss from natural calamities. Had tsunami been predicted in advance, the loss that happened could be minimized to a great extent.
Predicting weather a few days in advance may prove very useful to farmers and to the crew of ships, pilots, fishermen, defence personnel, etc.
Q2.Explain in short about Wind Vane. Answer: Purpose: Wind vane is a device used to measure the direction of the wind. Structure: The wind vane is a light-weight revolving plate with an arrowhead on one end and two metal plates attached to the other end at the same angle. This revolving plate is mounted on a rod in such a manner that it is free to rotate on a horizontal plane. It responds even to a slight blow of wind. Important Aspect: The arrow always points towards the direction from which the wind blows.
Q3.Explain in short about Anemometer. Answer:
An anemometer is an instrument that measures wind speed and wind pressure. Anemometers are important tools for meteorologists, who study weather patterns. They are also important to the work of physicists, who study the way air moves. The most common type of anemometer has three or four cups attached to horizontal arms. The arms are attached to a vertical rod. As the wind blows, the cups rotate, making the rod spin. The stronger the wind blows, the faster the rod spins. The anemometer counts the number of rotations, or turns, which is used to calculate wind speed. Because wind speeds are not consistent—there are gusts and lulls-wind speed is usually averaged over a short period of time.
A similar type of anemometer counts the revolutions made by windmill-style blades. The rod of windmill anemometers rotates horizontally. Other anemometers calculate wind speed in different ways. A hot-wire anemometer takes advantage of the fact that air cools a heated object when it flows over it.
Q4.How do Weather observatories work in India? Answer: Each day weather maps are prepared for that day by the Meteorological Department from the data obtained from observations made at various weather stations across the world. In India, weather-related information is collected and published under the auspices of the Indian Meteorological Department, New Delhi, which is also responsible for weather forecasting.
The Indian Meteorological Department (IMD) was established in 1875, with its headquarters at Calcutta. The IMD headquarters are presently located at New Delhi.
Q5.Write a short note on Stevenson Screen. Answer: The Stevenson screen is designed to protect thermometers from precipitation and direct sunlight while allowing air to circulate freely around them. Formation: It is made from wood with louvered sides to allow free and even flow of air. It is painted white to reflect radiation. It stands on four legs and is about 3 feet 6 inches above the level of the ground. The legs must be sufficiently rigid and be buried sufficiently in the ground to prevent shaking.
The front panel is hinged at the bottom to form a door, which allows for maintenance and reading of the thermometers. The door of Stevenson screen is always towards the north in the northern hemisphere and towards the south in the southern hemisphere because direct sunrays also affect mercury.
Objective: The purpose of the Stevenson screen is to create a uniform temperature enclosure that closely represents the same temperature as the air outside.
Q6.What is aneroid barometer? How does it work? Answer: Aneroid barometer gets its name from the Greek word, aneros in which ‘a’ means ‘not’, ‘neros’ means ‘moisture’, hence aneroid means without liquid. It is a compact and portable instrument. It consists of a corrugated metal box made up of a thin alloy, sealed completely and made airtight after partial exhaustion of air.
It has a thin flexible lid, which is sensitive to changes of pressure. As the pressure increases, the lid is pressed inward, and this, in turn, moves a system of levers connected to a pointer, which moves clockwise over the graduated dial and gives higher reading. When the pressure decreases, the lid is pushed outward and the pointer moves counter clockwise, indicating lower pressure. Barograph works on the principle of aneroid barometer.
There are a number of vacuum boxes placed one above the other so that the displacement is large. A system of levers magnifies this movement which is recorded by a pen on a paper attached to a rotating drum. The readings of a barograph are not always accurate, and therefore, they are standardised by comparing them with a mercury barometer reading.
Q7.Explain about surface observatory in detail. Answer: A typical surface observatory has instruments for measuring and recording weather elements like temperature (maximum and minimum), air pressure,humidity, clouds, wind and rainfall. Information: Specialised observatories record elements like radiation, ozone atmospheric trace gases, pollution and atmospheric electricity. These observations are taken all over the globe at fixed times of the day as decided by the WMO and the use of instruments are made conforming to international standards, thus making observations globally compatible.
Different types of surface observatories in India: In India, meteorological observations are normally classified into five categories depending upon their instruments and the number of daily observations taken. The highest category is Class-I. Typical instrumental facility available in a Class-I observatory consists of the following: Maximum and minimum thermometers, Anemometer, and wind vane, Dry and Wet bulb thermometer, Rain gauge and Barometer.
Q8.Differentiate between:
(i) Wet bulb and dry bulb, Answer: The dry bulb and wet bulb thermometers are two identical thermometers fixed to a wooden frame. But they are different in following way:
Dry Bulb Thermometer
Wet Bulb Thermometer
It is used to measure lowest humidity
It is used to measure highest humidity.
The bulb of the dry bulb thermometer is kept uncovered and is exposed to the air
The bulb of the wet bulb thermometer is wrapped up with a piece of wet muslin, which is kept continuously moist by dipping a strand of it into a small vessel of distilled water.
Its temperature remains high.
The evaporation from the wet bulb lowers its temperature.
(ii) Aneroid Barometer and Mercury Barometer. Answer:
Aneroid Barometer
Mercury Barometer
Aneroid barometer gets its name from the Greek word, aneros in which ‘a’ means ‘not’, ‘neros’ means ‘moisture’, hence aneroid means without liquid. It is a compact and portable instrument.
Mercury barometer is an accurate instrument and is used as a standard. In it the atmospheric pressure of any place is balanced against the weight of a column of mercury in an inverted glass tube.
It is filled with alcohol
It is filled with mercury
It is used to measure lowest temperature.
It is used to measure highest temperature.
(iii) Centigrade and the Fahrenheit. Answer: Both are units of measuring temperature but they have some differences.
Centigrade
Fahrenheit
On the Centigrade thermometer, the temperature of melting ice is marked 0°C and that of boiling water as 100°C, and the interval between the two is divided into 100 equal parts.
On the Fahrenheit thermometer, the freezing and boiling points of water are graduated as 32°F and 212°F respectively.
Centigrade = (Fahrenheit -32)
Fahrenheit= Centigrade ×95 +32
Long Answer Type Questions:
Q1.How is information about weather and related facts collected organized and dispensed in India? Answer:
In India, weather-related information is collected and published under the auspices of the Indian Meteorological Department, New Delhi, which is also responsible for weather forecasting.
A typical surface observatory has instruments for measuring and recording weather elements like temperature (maximum and minimum), air pressure, humidity, clouds, wind and rainfall. Specialised observatories also record elements like radiation, ozone atmospheric trace gases, pollution and atmospheric electricity. These observations are taken all over the globe at fixed times of the day as decided by the WMO and the use of instruments are made conforming to international standards, thus making observations globally compatible. In India, meteorological observations are normally classified into five categories depending upon their instruments and the number of daily observations taken. The highest category is Class-I.
Typical instrumental facility available in a Class-I observatory consists of the following:
Maximum and minimum thermometers
Anemometer and wind vane
Dry and Wet bulb thermometer
Rain gauge
Barometer
Observations are taken in these observatories normally at 00,03,06,09, 12,15,18,21 hours (Greenwich Mean Time) around the globe. However, for logistic reasons, some of the observatories take limited number of daily observations upper air observation during daytime only.
Weather satellites make comprehensive and large-scale observations of different meteorological elements at the ground level as well in the upper layers of the atmosphere. The geo-stationary satellites provide space-based observations about weather conditions. The Indian National Satellite (INSAT) provides valuable observations of temperature, cloud cover, wind and associated weather phenomena.
Q2.Explain the working of a barometer. Answer: The instrument used to measure atmospheric pressure is called a barometer. The unit of measurement is in the millibar. The most commonly used barometers are the mercury barometer, aneroid barometer and barographs. All the three work differently. Their working is explained below briefly:
1. Mercury barometer: It is an accurate instrument and is used as a standard. In it the atmospheric pressure of any place is balanced against the weight of a column of mercury in an inverted glass tube.
2.Aneroid barometer: It is a compact and portable instrument. It consists of a corrugated metal box made up of a thin alloy, sealed completely and made airtight after partial exhaustion of air. It has a thin flexible lid, which is sensitive to changes of pressure. As the pressure increases, the lid is pressed inward, and this, in turn, moves a system of levers connected to a pointer, which moves clockwise over the graduated dial and gives higher reading. When the pressure decreases, the lid is pushed outward and the pointer moves counter clockwise, indicating lower pressure.
3. Barograph: It works on the principle of aneroid barometer. There are a number of vacuum boxes placed one above the other so that the displacement is large. A system of levers magnifies this movement which is recorded by a pen on a paper attached to a rotating drum. The readings of a barograph are not always accurate, and therefore, they are standardised by comparing them with a mercury barometer reading.
Q3.Write short notes on the following: (i) Safe place for a thermometer (ii) Indian Daily Weather report Answer: (i) Safe place for thermometer: It is not safe to keep a thermometer in sunlight. We should also not keep it in airtight surroundings. The Stevenson screen is designed to protect thermometers from precipitation and direct sunlight while allowing air to circulate freely around them. It is made from wood with louvered sides to allow free and even flow of air. It is painted white to reflect radiation. The purpose of the Stevenson screen is to create a uniform temperature enclosure that closely represents the same temperature as the air outside.
It stands on four legs and is about 3 feet 6 inches above the level of the ground. The legs must be sufficiently rigid and be buried sufficiently in the ground to prevent shaking. The front panel is hinged at the bottom to form a door, which allows for maintenance and reading of the thermometers. The door of Stevenson screen is always towards the north in the northern hemisphere and towards the south in the southern hemisphere because direct sunrays also affect mercury.
(ii) Indian Daily Weather Report: IMD became a member of the World Meteorological Organization after independence on 27 April 1949. The agency has gained in prominence due to the significance of the monsoon rains on Indian agriculture. It plays a vital role in preparing the annual monsoon forecast, as well as in tracking the progress of the monsoon across India every season.
IMD undertakes observations, communications, forecasting and weather services. In collaboration with the Indian Space Research Organisation, the IMD also uses the IRS series and the Indian National Satellite System (INSAT) for weather monitoring of the Indian subcontinent. IMD was the first weather bureau of a developing country to develop and maintain its own satellite system. IMD is one of the 6 worldwide Regional Specialized Meteorological Centers of the Tropical Cyclone Programme of the World Weather Watch of the World Meteorological Organization. It is regional nodal agency for forecasting, naming and disseminating warnings about tropical cyclone in the Indian Ocean north of the Equator.
Q4.Explain the history of weather forecasting in India. Answer: In 1686, Edmond Halley published his treatise on the Indian summer monsoon, which he attributed to a seasonal reversal of winds due to the differential heating of the Asian land mass and the Indian Ocean. The first meteorological observatories were established in India by the British East India Company. These included the Calcutta Observatory in 1785, the Madras Observatory in 1796 and the Colaba Observatory in 1826. Several other observatories were established in India during the first half of the 19th century by various provincial governments.
After a tropical cyclone hit Calcutta in 1864, and the subsequent famines in 1866 and 1871 due to the failure of the monsoons, it was decided to organise the collection and analysis of meteorological observations under one roof. As a result, the Indian Meteorology Department was established in 1875. Henry Francis Blanford was appointed the first Meteorological Reporter of the IMD. In May 1889,Sir John Eliot was appointed the first Director General of Observatories in the erstwhile capital, Calcutta. The IMD headquarters were later shifted to Shimla in 1905, then to Pune in 1928 and finally to New Delhi in 1944.
Q5.Explain the instruments used to measure atmospheric pressure. Answer: A barometer is a scientific instrument used in meteorology to measure atmospheric pressure. A simple barometer consists of a long glass tube (closed at one end, open at the other) filled with mercury and turned upside down into a container of mercury. The barometer works by balancing the mercury in the glass tube against the outside air pressure, just like a set of scales. As air pressure increases—that is, as the air becomes heavier—it pushes more of the mercury up into the tube. As air pressure decreases, more of the mercury drains from the tube. So the level of mercury in the tube provides a precise measure of air pressure.
Mercury barometer is . an accurate instrument and is used as a standard. In it the atmospheric pressure of any place is balanced against the weight of a column of mercury in an inverted glass tube. Aneroid barometer is a compact and portable instrument. It consists of a corrugated metal box made up of a thin alloy, sealed completely and made airtight after partial exhaustion of air. It has a thin flexible lid, which is sensitive to changes of pressure. As the pressure increases, the lid is pressed inward, and this, in turn, moves a system of levers connected to a pointer, which moves clockwise over the graduated dial and gives higher reading.
When the pressure decreases, the lid is pushed outward and the pointer moves counterclockwise, indicating lower pressure. Barograph works on the principle of aneroid barometer. There are a number of vacuum boxes placed one above the other so that the displacement is large. A system of levers magnifies this movement which is recorded by a pen on a paper attached to a rotating drum. The readings of a barograph are not always accurate, and therefore, they are standardised by comparing them with a mercury barometer reading.
Q1.What is a scanner? How does it work? Answer: A scanner is usually made up of a reception system consisting of a mirror and detectors. A scanning sensor constructs the scene by recording a series of scan lines. While doing so, the motor device oscillates the scanning mirror through the angular field of view of the sensor, which determines the length of scan lines and is called swath. It is because of such reasons that the mode of collection of images by scanners is referred bit-by-bit. Each scene is composed of cells that determine the spatial resolution of an image. The oscillation of the scanning mirror across the scene directs the received energy to the detectors, where it is converted into electrical signals. These signals are further converted into numerical values called Digital Number (DN Values) for recording on a magnetic tape.
Q2.Explain about different types of sensor resolutions. Answer: Remote sensors are characterised by spatial, spectral and radiometric resolutions that enable the extraction of useful information pertaining to different terrain conditions.
1. Spatial Resolution: Spatial resolution of the sensors refers to the capability of the sensor to distinguish two closed spaced object surfaces as two different object surfaces. As a rule, with an increasing resolution the identification of even smaller object surfaces become possible,
2. Spectral Resolution: It refers to the sensing and recording power of the sensor in different bands of EMR (Electromagnetic radiation). Multispectral images are acquired by using a device that disperses the radiation received by the sensor and recording it by deploying detectors sensitive to specific spectral ranges. The principles in obtaining such images is the extension of the dispersion of light in nature resulting in the appearance of the “rainbow”.
3.Radiometric Resolution: It is the capability of the sensor to discriminate between two targets. Higher the radiometric resolution, smaller the radiance differences that can be detected between two targets.
Q3.How can we classify the characteristics of an object? Answer: We can group the characteristics of the objects into two broad categories, i.e. image characteristics and terrain characteristics.
Image Characteristics: The image characteristics include tone or colour in which objects appear, their shape, size, pattern, texture and the shadow they cast.
Terrain Characteristics: Location and the association of different objects with their surrounding objects constitute the terrain characteristics.
Q4.Differentiate between: (i) Photographs and images. Answer:
Basis
Photograph
Image
Meaning
A photograph refers specifically to images that have been recorded on photographic film.
An image refers to pictorial representation, regardless of what regions of energy have been used to detect and record it.
Scope
All photographs are images. Therefore it is inclusive in images and its scope is narrow.
All images are not photographs. Images can be: digital images and photographic images. Therefore, its scope is wider.
(ii) Whiskbroom Scanners and Pushbroom Scanners. Answer: Whiskbroom scanners, also sometimes referred to as spotlight or across track scanners, use a mirror to reflect light onto a single detector. The mirror moves back and forth, to collect measurements from one pixel in the image at a time. It is shown below: The moving parts make this type of sensor expensive and more likely to wear out.
Pushbroom Scanners: Pushbroom scanners are also sometimes referred to as along track scanners. It is used a line of detectors arranged perpendicular to the flight direction of the spacecraft. As the spacecraft flies forward, the image is collected one line at a time, with all of the pixels in a line being measured simultaneously. It is shown with the help of following figure. A pushbroom scanner receives a stronger signal than a whiskbroom scanner because it looks at each pixel area for longer. One drawback of pushbroom sensors is that the detectors in the “pushbroom” can have varying sensitivity. If they are not perfectly calibrated, this can result in stripes in the data. Sensors that use the push broom design include SPOT, IRS, QuickBird, OrbView etc.
(iii) Sun-synchronous (or polar) and geostationary orbits. Answer:
Basis
Sun-Synchronous
Geostationary Orbits
Location
Satellites in this orbit provide medium to high resolution images of the whole earth which are mostly used for environmental monitoring. They orbit at altitudes of 300 to 1,400 km above earth.
Geostationary orbits are located about 36,000 km above the earth.
Revolution time
With every satellite orbit which takes about 90 min, the earth is rotating a bit further resulting in the fact that the satellite is “watching” different sections of the earth in narrow bands. Days or weeks later, the satellite orbits again above the same section.
At this altitude a satellite needs exactly 24 hours to orbit around the earth, the same time the earth takes to perform a complete revolution around its axis.
Expansion
It is expaided from 81 degree north to 81 degree south latitude.
It is expanded on one third of the globe.
Example
The US LANDSAT series is a well known example of a polar orbiting satellite.
METEOSAT is one example for a geostationary satellite.
Utility
It is important for earth resources
It is important for telecommunication and weather department.
(iv) Photographic and non-photographic sensors. Answer:
Basis
Photographic sensors
Non-photographic Sensors
Meaning
A photographic sensor (camera) records the images of the objects at an instance of exposure.
A non-photographic sensor obtains the images of the objects in bit-by-bit form. These sensors are known as scanners.
Device
It is done through camera
It is done through scanners
Other name
It is also called Analogue sensors
It is also called digital sensors.
(v) Photographic image and digital image Answer:
Basis
Photographic Image
Digital Image
Meaning
Photographs are acquired in the optical regions of the electromagnetic spectrum, i.e. 0.3 – 0.9 pm.
A digital image consists of discrete picture elements called pixels. Each one of the pixels in an image has an intensity value and an address in two dimensional image space.
Colour
Four different types of light sensitive film emulsion bases are used to obtain photographs. These are black and white, colour, black and white infrared and colour infrared.
It does not require any film.
Long Answer Type Questions:
Q1.How does remote sensing help in the collection of information about the properties of the objects and phenomena of the earth surface? Answer: Remote sensing help in the collection of information about the properties of the objects and phenomena of the earth surface:
1. Source of Energy: Sun is the most important source of energy used in remote sensing.
2. Transmission of Energy from the Source to the Surface of the Earth: The energy that emanates from a source propagates between the source and the object surface in the form of waves of energy at a speed of light (300,000 km per second). Such energy propagation is called Electromagnetic Radiation (EMR).
3. Interaction of Energy with the Earth’s Surface: The propagating energy finally interacts with the objects of the surface of the earth. This leads to absorption, transmission, reflection or emission of energy from the objects.
4. Propagation of Reflected/Emitted Energy through Atmosphere: When energy is reflected from objects of the earth’s surface, it re-enters into the atmosphere.
5. Detection of Reflected/Emitted Energy by the Sensor: The sensors recording the energy that they receive are placed in a near-polar sun-synchronous orbit at an altitude of 700 – 900 km. These satellites are known as remote sensing satellites (e.g. Indian Remote Sensing Series). As against these satellites, the weather monitoring and telecommunication satellites are placed in a Geostationary position (the satellite is always positioned over its orbit that synchronizes with the direction of the rotation of the earth) and revolves around the earth (coinciding with the direction of the movement of the earth over its axis) at an altitude of nearly 36,000 km (e.g. INSAT series of satellites).
6. Conversion of Energy Received into Photographic/Digital Form of Data: The radiations received by the sensor are electronically converted into a digital image. It comprises digital numbers that are arranged in rows and columns. These numbers may also be converted into an analogue (picture) form of data product. The sensor onboard an earth¬orbiting satellite electronically transmits the collected image data to an Earth Receiving Station located in different parts of the world.
7. Extraction of Information Contents from Data Products: After the image data is received at the earth station, it is processed for elimination of errors caused during image data collection. Once the image is corrected, information extraction is carried out from digital images using digital image processing techniques and from analogue form of data products by applying visual interpretation methods.
8. Conversion of Information into Map/Tabular Forms: The interpreted information is finally delineated and converted into different layers of thematic maps. Besides, quantitative measures are also taken to generate tabular data.
Q2.Explain about different types of multispectral scanners. Answer: In satellite remote sensing, the Multi-Spectral Scanners (MSS) are used as sensors. These sensors are designed to obtain images of the objects while sweeping across the field of view. The Multi-Spectral Scanners are divided into the following types:
Whiskbroom Scanners
Pushbroom Scanners
1. Whiskbroom Scanners: The whiskbroom scanners are made up of a rotating mirror and a single detector. The mirror is so oriented that when it completes a rotation, the detector sweeps across the field of view between 90° and 120° to obtain images in a large number of narrow spectral bands ranging from visible to middle infrared regions of the spectrum. The total extent of the oscillating sensor is known as the Total Field of View (TFOV) of the scanner. While scanning the entire field, the sensor’s optical head is always placed at a particular dimension called the Instantaneous Field of View (IFOV).
2. Pushbroom Scanners: The pushbroom scanners consist of a number of detectors which are equivalent to the number obtained by dividing the swath of the sensor by the size of the spatial resolution. In pushbroom scanner, all detectors are linearly arrayed and each detector collects the energy reflected by the ground cell (pixel) dimensions of 20 metres at a nadir’s view. For example, the swath of High-Resolution Visible Radiometer – 1 (HRVR – 1) of the French remote sensing satellite SPOT is 60 km and the spatial resolution is 20 metres. If we divide 60 km x 1000 metres/20 metres, we get a number of 3000 detectors that are deployed in SPOT HRV – 1 sensor.
Q3.Based upon the mechanism used in detecting and recording, in how many categories can we classify the remotely sensed data products? Answer: Based upon the mechanism used in detecting and recording, these may be broadly classified into two types:
Photographic Images
Digital Images
1. Photographic Images: Photographs are acquired in the optical regions of electromagnetic spectrum, i.e. 0.3-0. 9 pm. Four different types of light sensitive film emulsion bases are used to obtain photographs. These are black and white, colour, black and white infrared and colour infrared. However, in aerial photography black and white film is normally used. Photographs may be enlarged to any extent without loosing information contents or the contrast.
2. Digital Images: A digital image consists of discrete picture elements called pixels. Each one of the pixels in an image has an intensity value and an address in two-dimensional image space. A digital number (DN) represents the average intensity value of a pixel. It is dependent upon the electromagnetic energy received by the sensor and the intensity levels used to describe its range. In a digital image, the reproduction of the details pertaining to the images of the objects is affected by the size of the pixel. A smaller size pixel is generally useful in the preservation of the scene details and digital representation. However, zooming of the digital image beyond certain extent produces loss of information and the appearance of pixels only. Using a digital image processing algorithms, the digital numbers representing their intensity level in an image may be displayed.
Q4.Explain various elements of visual interpretation. Answer: Elements of Visual Interpretation Whether we are conscious of it or not we use the form, size, location of the objects and their relationships with the surrounding objects to identify them in our day-to-day life. These characteristics of objects are termed as elements of visual interpretation.
1. Tone or Colour: All objects receive energy in all regions of spectrum. The interaction of EMR with the object surface leads to the absorption, transmittance and reflection of energy. It is the reflected amount of the energy that is received and recorded by the sensor in tones of grey, or hues of colour in black and white, and colour images respectively. The variations in the tone or the colour depend upon the orientation of incoming radiations, surface properties and the composition of the objects.
2. Texture: The texture refers to the minor variations in tones of grey or hues of colour. These variations are primarily caused by an aggregation of smaller unit features that fail to be discerned individually such as high density and low density residential areas; slums and squatter settlements; garbage and other forms of solid waste; and different types of crops and plants. The textural differences in the images of certain objects vary from smooth to coarse textures.
3. Size: The size of an object as discerned from the resolution or scale of an image is another important characteristic of individual objects. It helps in distinctively identifying the industrial and industrial complexes with residential dwellings.
4. Shape: The general form and configuration or an outline of an individual object provides important clues in the interpretation of remote sensing images. The shape of some of the objects is so distinctive that make them easy to identify. For example, the shape of the Sansad Bhawan is typically distinct from many other built- up features.
5. Shadow: Shadow of an object is a function of the sun’s illumination angle and the height of the object itself. The shape of some of the objects is so typical that they could not be identified without finding out the length of the shadow they cast. For example, the Question utub Minar located in Delhi, minarets of mosques, overhead water tanks, electric or telephone lines, and similar features can only be identified using their shadow.
6. Pattern: The spatial arrangements of many natural and man-made features show repetitive appearance of forms and relationships. The arrangements can easily be identified from the images through the utilisation of the pattern they form. For example, planned residential areas with the same size and layout plan of the dwelling units in an urban area can easily be identified if their pattern is followed.
7. Association: The association refers to the relationship between the objects and their surroundings along with their geographical location. For example, an educational institution always finds its association with its location in or near a residential area as well as the location of a playground within the same premises.
Q1.What are the advantages of aerial photographs? Answer: Given below are the advantages of aerial photographs:
The photographs taken from ground provide us with a view of the object similar to the way we see them with our own eyes. In other words, we get a horizontal perspective of the objects photographed. Aerial photography provides a bird’s eye view of large areas, enabling us to see features of the earth surface in their spatial context.
An aerial photograph is a record of the surface features at an instance of exposure. Therefore, it can be used as a historical record.
The sensitivity of the film used in taking aerial photographs is relatively more than the sensitivity of the human eyes. Our eyes perceive only in the visible region of the electromagnetic spectrum, i. e. 0.4 to 0.7 pm whereas the sensitivity of the film ranges from 0.3 to 0.9 pm.
Aerial photographs are generally taken with uniform exposure interval. It enables us in obtaining stereo pair of photographs.
Such a pair of photographs also helps us in getting a three-dimensional view of the surface photographed.
Q2.The distance between two points on an aerial photograph is measured as 2 centimetres. The known distance between the same two points on the ground is 1 km. Compute the scale of the aerial photograph (Sp). Answer: Sp = Dp : Dg = 2 cm :1 km = 2cm : 1 x 100,000 cm = 1 : 100,000/2 = 50,000 cm = 1 unit represents 50,000 units Therefore, Sp = 1: 50,000.
Q3.The distance measured between two points on a map is 2 cm. The corresponding distance on an aerial photograph is 10 cm. Calculate the scale of the photograph when the scale of the map is 1: 50,000. Answer: Photo scale (Sp) = Photo distance (Dp) : Map distance (Dm) x Map scale factor (msf) = 10 cm : 2 cm x 50,000 = 10 cm : 100,000 cm = 1 : 100,000/10 = 10,000 cm = 1 unit represents 10,000 units Therefore, Sp = 1: 10,000
Q4.Compute the scale of an aerial photograph when the flying height of the aircraft is 7500 m and the focal length of the camera is 15 cm. Answer: Focal Length (f) : Flying Height (H) = Photo distance (Dp) : Ground distance (Dg) Sp = f: H Or Sp = 15 cm : 7,500 x 100 cm Or Sp = 1 : 750,000/15 Therefore, Sp = 1 : 50,000
Q5.Differentiate between: (i) Aerial photograph and map. (it) Aerial photographs and satellite images. (iii) High oblique photograph and low oblique photograph. (iv) Vertical photograph and high oblique photograph. (v) Vertical photograph and low oblique photograph. Answer: (i)
Basis
Aerial Photograph
Map
Projection
It is a central Projection.
It is an orthogonal Projection.
Accuracy
An aerial photograph is geometrically incorrect. The distortion in the geometry is minimum at the centre and increases towards the edges of the photographs.
A map is geometrically correct representation of the part of the earth projected.
Scale
The scale of the photograph is not uniform.
The scale of the map is uniform throughout the map extent.
Impact of enlargement or reduction
Enlargement/reduction does not change the contents of the photographs and can easily be carried out.
Enlargement/reduction of the maps involves redrawing it afresh.
Utility
Aerial photography holds good for inaccessible and inhospitable areas.
The mapping of inaccessible and inhospitable areas is very difficult and sometimes it becomes impossible.
(ii)
Basis
Aerial Photographs
Satellite Images
Meaning
These are taken from an aeroplane or helicopter.
These are taken from man-made satellite launched in space.
Accuracy
These are less accurate as compared to satellite images.
These are more accurate as compared to aerial images.
Suitability
These are suitable for taking photographs of the earth.
These are used for taking photographs of other planets and celestial bodies.
Utility
Aerial photography holds good for inaccessible and inhospitable areas of the earth
It is useful in knowing climatic condition and weather forecast.
Disastermanagement
It is more useful in disaster management for providing relief.
It is more useful in disaster management by predicting weather and taking preventive actions.
(iii)
Basis
High Oblique Photograph
Low Oblique Photograph
Optical Axis
Deviation is more than 300 degree from the vertical axis.
Deviation is more than 30 degree from the vertical axis.
Coverage
It covers largest area.
It covers larger area.
Difference in comparison to map
It is greatest with high oblique photographs.
It is greater with low oblique photographs.
Utility
It is useful in illustrative comparison.
It is useful in recoqnaissance survey.
(iv)
Basis
Vertical Photograph
High Oblique Photograph
Optical Axis
Tilt< 3 degree i.e. exactly or nearly coincides with the vertical axis.
Deviation is more than 300 degree from the vertical axis.
Horizon
Horizon does not appear
Horizon does appear
Coverage
It covers small area.
It covers largest area.
Scale
Scale is uniform if the terrain is flat.
Scale keeps decreasing from foreground to background.
Difference in comparison to map
It is least with vertical photographs.
It is greatest with high oblique photographs.
Utility
It is useful in topographical and thematic mapping.
It is useful in illustrative comparison.
(v)
Basis
Vertical Photograph
Low Oblique Photograph
Optical Axis
Tilt< 3 degree i.e. exactly or nearly coincides with the vertical axis.
Deviation is more than 30 degree from the vertical axis.
Horizon
Horizon does not appear
Horizon does appear
Coverage
It covers small area.
It covers comparatively larger area.
Scale
Scale is uniform if the terrain is flat.
Scale keeps decreasing from foreground to background.
Difference in comparison to map
It is least with vertical photographs.
It is relatively greater with low oblique photographs.
Utility
It is useful in topographical and thematic mapping.
It is useful in reconnaissance survey.
Long Answer Type Questions:
Q1.Explain about different types of aerial photographs on the basis of position of camera axis. Answer: Types of Aerial Photographs Based on the Position of the Cameral Axis: 1. Vertical Photographs: While taking aerial photographs, two distinct axes are formed from the camera lens centre, one towards the ground plane and the other towards the photo plane. The perpendicular dropped from the camera lens centre to the ground plane is termed as the vertical axis, whereas the plumb line drawn from the lens centre to the photo plane is known as the photographic/optical axis. When the photo plane is kept parallel to the ground plane, the two axes also coincide with each other. The photograph so obtained is known as vertical aerial photograph
2. Low Oblique: An aerial photograph taken with an intentional deviation of 15° to 30° in the camera axis from the vertical axis is referred to as the low oblique photograph. This kind of photograph is often used in reconnaissance surveys. It is shown with the help of following figure.
3. High Oblique: The high oblique are photographs obtained when the camera axis is intentionally inclined about 60° from the vertical axis. Such photography is useful in illustrative surveys. It is shown with the help of following figure.
Q2.How can we classify aerial photographs on the basis of scale? Answer: There are three types of Aerial Photographs Based on Scale.
Large Scale Photographs: When the scale of an aerial photograph is 1:15,000 and larger, the photography is classified as large-scale photograph. It is shown with the help of following figure.
Medium Scale Photographs: The aerial photographs with a scale ranging between 1 : 15,000 and 1 : 30,000 are usually treated as medium scale photographs as shown in the figure given below:
Small Scale Photographs: The photographs with the scale being smaller than 1 : 30,000, are referred to as small scale photographs as shown in the figure.
Q3.Explain in detail about aerial photographs and satellite images. Answer: These days, it has become very easy to draw’ maps and interpret them through aerial photographs and satellite images. It requires a special type of training to understand and interpret aerial photographs. Many countries are making use of aerial photographs not only for defence purposes but also for planning land use, development of cities and towns, development of multipurpose projects etc.
Satellite images are used to predict climatic conditions. It becomes easy to predict weather by using satellite images, wre can find mineral availability, land use plan by making use of satellite images.
Q4.Explain different types of projection. Answer: There are three types of projection: 1. Parallel Projection: In this projection, the projecting rays are parallel but not necessarily perpendicular. The triangle ABC is projected on LL1 as triangle abc.
2. Orthogonal Projection: This is a special case of parallel projections. Maps are orthogonal projections of the ground. The advantage of this projection is that the distances, angles or areas on the plane are independent of the elevation differences of the objects. In the figure given below an orthogonal projection is where the projecting rays are perpendicular to the line LL1
3. Central Projection: Figure given below shows an example of Central Projection. In this figure the projecting rays Aa, Bb and Cc pass through a common point O, which is called the perspective Centre. The image projected by a lens is treated like a central projection. An aerial photograph, as discussed earlier is a central projection. In an absolutely vertical flat terrain the aerial photograph will be geometrically the same as the corresponding map of the area. However, because of the tilt of the photograph and relief variations of the ground photographed, an aerial photograph differs geometrically from the map of the corresponding area.
Q1.What are the features of contours? Answer: Some basic features of contour lines are:
A contour line is drawn to show places of equal heights.
Contour lines and their shapes represent the height and slope or gradient of the landform.
Space between contour lines represents slope. Closely spaced contours represent steep slopes while widely spaced contours represent gentle slope.
When two or more contour lines merge with each other, they represent features of vertical slopes such as cliffs or waterfalls.
Two contours of different elevation usually do not cross each other.
Q2.Explain how do we interpret a topographical sheet? Answer: It is essential to have knowledge of map language and sense of direction are essential in reading and interpreting topo-sheets. We must first look for the northline and the scale of the map and orient ourselves accordingly. We must have a thorough knowledge of the legends / key given in the map depicting various features. All topo-sheets contain a table showing conventional signs and symbols used in the map. We must be acquainted with conventional symbols, signs and colours.
Q3.Under which heads is a topographical sheet interpreted? Explain each in short. Answer: A topographic sheet is usually interpreted under the following way:
Marginal Information: It includes the topographical sheet number, its location, grid references, its extent in degrees and minutes, scale, the districts covered, etc.
Relief of the Area: The general topography of the area is studied to identify different landforms along with peaks, ridges, spur and the general direction of the slope.
Drainage of the Area: We also need to interpret the important rivers and their tributaries and the type and extent of valleys formed by them, the types of drainage pattern, i.e. dendritic, radial, ring, trellis, internal, etc.
Land Use: It includes the use of land under different categories like Natural vegetation and forest which part of the area is forested, whether it is dense forest or thin, and the categories of the forest found there like Reserved, Protected, Classified / Unclassified.
Transport and Communication: The means of transportation include national or state highways, districts roads, cart tracks, camel tracks, footpaths, railways, waterways, major communication lines, post offices, etc. topographical sheet presents each of these.
Settlement: Settlements are studied under rural settlements and urban settlements.
Occupation: The general occupation of the people of the area may be identified with the help of land use and the type of settlement.
Q4.What factors determine the site of settlements? Answer: Various factors determine the site of settlements like
Source of water
Provision of food
Nature of relief
Nature and character of occupation
Defence.
Q5.Write a short note on map interpretation. Answer: Map interpretation involves the study of factors that explain the causal relationship among several features shown on the map. For example, the distribution of natural vegetation and cultivated land can be better understood against the background of landform and drainage. Likewise, the distribution of settlements can be examined in association with the levels of transport network system and the nature of topography.
Long Answer Type Questions:
Q1.Explain the steps involved in drawing, a Cross-section from their contours in different topographical landforms. Answer: The following steps may be followed to draw cross-sections of various relief features from their contours:
Draw a straight line cutting across the contours on the map and mark it as XY.
Take a strip of white paper or graph and place its edge along the XY line.
Mark the position and value of every contour that cuts the line XY.
Choose a suitable vertical scale, e.g. V2 cm =100 metres, to draw horizontal lines parallel to each other and equal to the length of XY. The number of such lines should be equal or more than the total contour lines.
Label the appropriate values corresponding to the contour values along the vertical of the cross-section. The numbering may be started with the lowest value represented by the contours.
Place the edge of the marked paper along the horizontal line at the bottom line of the cross-section in such a way that XY of the paper corresponds to the XY of the map and mark the contour points.
Draw perpendiculars from XY line, intersecting contour lines, to the corresponding line at the cross-section base.
Smoothly join all the points marked on different lines at the cross-section base.
Q2.Under which heads are topographical maps explained? Answer: A topographic sheet is usually interpreted in the following way:
Marginal Information: It includes the topographical sheet number, its location, grid references, its extent in degrees and minutes, scale, the districts covered, etc.
Relief of the Area: The general topography of the area is studied to identify different landforms along with peaks, ridges, spur and the general direction of the slope. These features are studied under the following heads:
Hill: With concave, convex, steep or gentle slope and shape.
Plateau: Whether it is broad, narrow, flat, undulating or dissected.
Plain: Its types, i.e. alluvial, glacial, karst, poastal, marshy, etc.
Mountain: General elevation, peak, passes, etc.
Drainage of the Area: We also need to interpret the important rivers and their tributaries and the type and extent of valleys formed by them, the types of drainage pattern, i.e. dendritic, radial, ring, trellis, internal, etc.
Land Use: It includes the use of land under different categories like Natural vegetation and forest, which part of the area is forested, whether it is dense forest or thin, and the categories of forest found there like Reserved, Protected, Classified / Unclassified.
Transport and Communication: The means of transportation include national or state highways, district roads, cart tracks, camel tracks, footpaths, railways, waterways, major communication lines, post offices, etc. topographical sheet presents each of these.
Settlement: Settlements are studied under the following heads:
Rural Settlements: The types and patterns of rural settlements, i.e. compact, semi-compact, dispersed, linear, etc.
Urban Settlements: Type of urban settlements and their functions, i.e. capital cities, administrative towns, religious towns, port towns, hill stations, etc.
Occupation: The general occupation of the people of the area may be identified with the help of land use and the type of settlement. For example, in rural areas the main occupation of majority of the people is agriculture; in tribal regions, lumbering and primitive agriculture dominates and in coastal areas, fishing is practised. Similarly, in cities and towns, services and business appear to be the major occupations of the people.
Q3.Explain about identification of cultural features from topographical sheets Answer: Settlements, buildings, roads and railways are important cultural features shown on topographical sheets through conventional signs, symbols and colours. The location and pattern of distribution of different features help in understanding the area shown on the map. Types of Settlements: Four types of rural settlements may be identified on the map:
Compact
Scattered
Linear
Circular
Urban centres are distinguished as:
Cross-road town
Nodal point
Market centre
Hill station
Coastal resort centre
Port
Manufacturing centre with suburban villages or satellite towns
Capital town
Religious centre
Site of settlements: It should be closely examined with reference to the contour and drainage map. Density of settlement is directly related to food supply. Sometimes, village settlements form alignments, i.e. they are spread along a river valley, road, embankment, coastline – these are called linear settlements. In the case of an urban settlement, a cross-road town assumes a fan-shaped pattern, the houses being arranged along the roadside and the crossing being at the heart of the town and the main market place. In a nodal town, the roads radiate in all directions.
Transport and Communication Pattern: Relief, population, size and resource development pattern of an area directly influence the means of transport and communication and their density. These are depicted through conventional signs and symbols. Means of transport and communication provide useful information about the area shown on the map.
Q1.How are conical projections drawn? Answer: A Conical projection is drawn by wrapping a cone round the globe and the shadow of graticule network is projected on it. When the cone is cut open, a projection is obtained on a flat sheet. A conical projection is one, which is drawn by projecting the image of the ‘ graticule of a globe on a developable cone, which touches the globe along a parallel of latitude called the standard parallel. As the cone touches the globe located along AB, the position of this parallel on the globe coinciding with that on the cone is taken as the standard parallel. The length of other parallels on either side of this parallel are distorted.
Q2.What is map projection? Answer: It is the system of transformation of the spherical surface onto a plane | surface. It is carried out by an orderly and systematic representation of the parallels of latitude and the meridians of longitude of the spherical earth or part of it on a plane surface on a conveniently chosen scale. In map projection we try to represent a good model of any part of the earth in its true shape and dimension. But distortion in some form or the other is inevitable.
To avoid this distortion, various methods have been devised and many types of projections are drawn. Due to this reason, map projection is also defined as the study of different methods which have been tried for transferring the lines of graticule from the globe to a flat sheet of paper.
Q3.What are the qualities and limitations of a globe? Answer: Qualities of globe can be expressed as follows:
A globe is the best model of the earth. Due to this property of the globe, the shape and sizes of the continents and oceans are accurately shown on it.
It shows the directions and distances very accurately.
The globe is divided into various segments by the lines of latitude and longitude.
Limitations:
It is expensive.
It can neither be carried everywhere easily nor can a minor detail be shown on it.
Besides, on the globe the meridians are semi-circles and the parallels are circles. When they are transferred on a plane surface, they become intersecting straight lines or curved lines.
Q4.Classify the projections on the basis of method of construction. Answer: On the basis of method of construction, projections are generally classified into perspective, non-perspective and conventional or mathematical.
Perspective projections: These can be drawn taking the help of a source of light by projecting the image of a network of parallels and meridians of a globe on developable surface.
Non-perspective projections: These are developed without the help of a source of light or casting shadow on surfaces, which can be flattened.
Mathematical or conventional projections: These are those, which are derived by mathematical computation and formulae and have little relations with the projected image.
Q5.Classify projections on the basis of global properties. Answer: On the basis of global properties, projections are classified into:
Equal Area Projection
Orthomorphic Projection,
Azimuthal Projection and
Equidistant Projections.
Equal Area Projection: It is also called homolographic projection. It is that projection in which areas of various parts of the earth are represented correctly.
Orthomorphic or True-Shape projection: It is one in which shapes of various areas are portrayed correctly. The shape is generally maintained at the cost of the correctness of area.
Azimuthal or True-Bearing projection: It is one on which the direction of all points from the centre is correctly represented.
Equidistant or True Scale projection: It is that where the distance or scale is correctly maintained.
However, there is no such projection, which maintains the scale correctly throughout. It can be maintained correctly only along some selected parallels and meridians as per the requirement.
Q6.Write a short note on developable surface and zenithal projections. Answer: A developable surface is one, which can be flattened, and on which, a network of latitude and longitude can be projected. A cylinder, a cone and a plane have the property of developable surface. On the basis of nature of developable surface, the projections are classified as cylindrical, conical and zenithal projections.
1. Cylindrical Projections: These are made through the use of cylindrical developable surface. A paper-made cylinder covers the globe, and the parallels and meridians are projected on it.
2. Zenithal projection: It is directly obtained on a plane surface when plane touches the globe at a point and the graticule is projected on it. Generally, the plane is so placed on the globe that it touches the globe at one of the poles. These projections are further subdivided into normal, oblique or polar as per the position of the plane touching the globe.
Normal Projection: If the developable surface touches the globe at the equator, it is called equatorial or normal projection.
Oblique Projection: If it is tangential to a point between the pole and the equator, it is called the oblique projection;
Polar Projection: If it is tangential to the pole, it is called the polar projection.
Q7.What is the need of map projection? Answer: The need for a map projection mainly arises to have a detailed study of a region, which is not possible to do from a globe. Similarly, it is not easy to compare two natural regions on a globe. Therefore, drawing accurate large-scale maps on a flat paper is required. It gives birth to a problem. The problem is how to transfer these lines of latitude and longitude on a flat sheet. If we stick a flat paper over the globe, it will not coincide with it over a large surface without being distorted. If we throw light from the centre of the globe, we get a distorted picture of the globe in those parts of paper away from the line or point over which it touches the globe.
The distortion increases with increase in distance from the tangential point. So, tracing all the properties like shape, size and directions, etc. from a globe is nearly impossible because the globe is not a developable surface.
Map projection helps to solve this problem. In map projection we try to represent a good model of any part of the earth in its true shape and dimension. But distortion in some form or the other is inevitable. To avoid this distortion, various methods have been devised and many types of projections are drawn. Due to this reason, map projection is also defined as the study of different methods which have been tried for transferring the lines of graticule from the globe to a flat sheet of paper.
Long Answer Type Questions:
Q1.Explain the qualities of Mercator projection. Answer: Mercator’s Projection is very useful for navigational purposes. A Dutch cartographer Mercator Gerardus Karmer developed this projection in 1569. The projection is based on mathematical formulae. Properties:
It is an orthomorphic projection in which the correct shape is maintained.
The distance between parallels increases towards the pole.
Like cylindrical projection, the parallels and meridians intersect each other at right angle. It has the characteristics of showing correct directions.
A straight line joining any two points on this projection gives a constant bearing, which is called a Laxodrome or Rhumb line.
All parallels and meridians are straight lines and they intersect each other at right angles.
All parallels have the same length which is equal to the length of equator.
All meridians have the same length and equal spacing. But they are longer than the corresponding meridian on the globe.
Spacing between parallels increases towards the pole.
Scale along the equator is correct as it is equal to the length of the equator on the globe; but other parallels are longer than the corresponding parallel on the globe; hence the scale is not correct along them.
Shape of the area is maintained, but at the higher latitudes distortion takes place.
The shape of small countries near the equator is truly preserved while it increases towards poles.
It is an azimuthal projection.
This is an orthomorphic projection as scale along the meridian is equal to the scale along the parallel.
Q2.Explain properties, limitations and uses of cylindrical equal area projection. Answer: The cylindrical equal area projection is also known as the Lambert’s projection. It has been derived by projecting the surface of the globe with parallel rays on a cylinder touching it at the equator. Both the parallels and meridians are projected as straight lines intersecting one another at right angles. The pole is shown with a parallel equal to the equator; hence, the shape of the area gets highly distorted at the higher latitude.
Properties
All parallels and meridians are straight lines intersecting each other at right angle.
Polar parallel is also equal to the equator.
Scale is true only along the equator.
Limitations
Distortion increases as we move towards the pole.
The projection is non-orthomorphic.
Equality of area is maintained at the cost of distortion in shape.
Uses
The projection is most suitable for the area lying between 45° N and S latitudes.
It is suitable to show the distribution of tropical crops like rice, tea, coffee, rubber and sugarcane.
Q3.Explain properties of Conical Projection with one Standard Parallel. Answer: A conical projection is one, which is drawn by projecting the image of the graticule of a globe on a developable cone, which touches the globe along a parallel of latitude called the standard parallel. As the cone touches the globe located along AB, the position of this parallel on the globe coinciding with that on the cone is taken as the standard parallel.
Properties
All the parallels are arcs of concentric circle and are equally spaced.
All meridians are straight lines merging at the pole. The meridians intersect the parallels at right angles.
The scale along all meridians is true.
An arc of a circle represents the pole.
The scale is true along the standard parallel but exaggerated away from the standard parallel.
Meridians become closer to each other towards the pole.
This projection is neither equal area nor orthomorphic.
Q4.Explain the limitations and uses of Conical Projection with one Standard Parallel. Answer: Limitations
It is not suitable for a world map due to extreme distortions in the hemisphere opposite the one in which the standard parallel is selected.
Even within the hemisphere, it is not suitable for representing larger areas as the distortion along the pole and near the equator is larger.
Uses
This projection is commonly used for showing areas of mid-latitudes with limited latitudinal and larger longitudinal extent.
A long narrow strip of land running parallel to the standard parallel and having east-west stretch is correctly shown on this projection.
Direction along standard parallel is used to show railways, roads, narrow river valleys and international boundaries.
This projection is suitable for showing the Canadian Pacific Railways, Trans- Siberian Railways, international boundaries between USA and Canada and the Narmada Valley.
Q5.Prepare graticule for a Cylindrical Equal Area Projection for the world when R.F. is 1: 300,000,000 and the interval is 15° apart. Answer: Construction
Draw a circle of 2.1 cm radius;
Mark the angles of 15°, 30°, 45°, 60°, 75° and 90° for both, northern and southern hemispheres;
Draw a line of 13.2 cm and divide it into 24 equal parts at a distance of 0.55cm apart.
This line represents the equator;
Draw a line perpendicular to the equator at the point where 0° is meeting the circumference of the circle;
Extend all the parallels equal to the length of the equator from the perpendicular line; and Complete the projection as shown in figure given below:
Q6.Draw a Mercator Projection for the world map when the R.F. is 1:250,000,000 and the interval between the latitude and longitude is 15°. Answer: Calculation: Radius of the reduced earth R is “1 is 1: 250,000,000 Length of the equator 2πR or
1 × 227 × 2=6.28 inches
Construction
Draw a line of 6.28″ inches representing the equator as Equation.
Divide it into 24 equal parts. Determine the length of each division using the following formula: Length of the equator multiplied by interval divided by 360°.
Calculate the distance for latitude with the help of the table given below: Latitude Distance 15° 0.25 x 1 = 0.25″ inch 30° and so on, Complete the projection as shown in Figure given below:
Q1.When it is 12:00 noon in Greenwich then what will be the time at Thimbu, capital of Bhutan which is located at 90° east? Answer:
At one degree time changes by 4 minutes Difference between Greenwich and Thimbu is equal to 90° Therefore time difference = 90 x 4 = 360 minutes = 6 hours (360/60)
Q2.When it is 12:00 noon in Greenwich then what will be the time at New Orleans which is located at 90° west? Answer: At one degree time changes by 4 minutes Difference between Greenwich and New Orleans is equal to 90° Therefore time difference = 90 x 4 = 360 minutes = 6 hours (360/60) Since it is towards, west, time will decrease by 4 minutes on each longitude. Therefore, it will be 6 am in the morning.
Q3.When it is 12:00 noon in Greenwich then what will be the time at New York which is located at 74° west? Answer: At one degree time changes by 4 minutes Difference between Greenwich and New York is equal to 74° Therefore time difference = 74 x 4 = 296 minutes = 4 hours 56 minutes (296/60) Since it is towards, west, time will decrease by 4 minutes on each longitude. Therefore, it will be 7:04 am in the morning.
Q4.What is International Date Line? What is its importance? Answer: The world is divided into 24 time zones, there has to be a place where there is a difference in days, somewhere the day truly “starts” on the planet. The 180° line of longitude is approximately where the International Date Line passes. The time at this longitude is exactly 12 hours from the 0° longitude, irrespective of one travels westward or eastward from the Prime Meridian. Time decreases east of the Prime Meridian and increases to its west. Hence, for a person moving east of the Prime Meridian, the time would be 12 hours less than the time at 0° longitude. For another person moving westward, the time would be 12 hours more than the Prime Meridian. For example, a person moving eastward on Tuesday will count the day as Wednesday once [ the International Date Line is crossed. Similarly, another person starting his journey on the same day, but moving westward will count the day as Monday after crossing the line.
Long Answer Type Questions:
Q1.Explain the relationship between r longitude and time, Answer: The earth rotates from west to east over its axis. It makes the sun rise in the east and set in the west. The rotation of the earth over its axis takes 24 hours to complete one circle or 360° of longitudes. As 180° of longitudes fall both east and west of the Prime Meridian, the sun, thus takes 12 hours’ time to traverse the eastern and western hemispheres. In other words, the sun traverses 15° of longitudes per hour or one degree of longitude in every four minutes of time. The time decreases when we move from west to east and increases with our westward movement. The rate of the time at which the sun traverses over certain degrees of longitudes is used to determine the local time of an area with respect to the time at the Prime Meridian (0°Longitude). For example when it is 2 pm in Greenwich, it will be 3 pm in 15° east. (15×4 = 60 minutes = 1 hour).
Q2.Explain the process or drawing latitudes. Answer: Process of drawing latitudes:
Draw a circle.
Divide it into two equal halves by drawing a horizontal line in the centre. This represents the equator.
Place a protractor on this circle in a way that 0° and 180° line on the protractor coincide with the equator on the paper.
Now to draw 20°S, mark two points at an angle of 20° from the equator, east and west in the lower half of the circle.
The arms of the angle cut the circle at two points. Join these two points by a line parallel to the equator. It will be 20°S.
Q3.Explain the process of drawing longitudes Ans. Process of drawing longitudes: Answer:
Draw a circle whose centre represents the North Pole. The circumference will represent the equator.
Draw a vertical line through the centre of the circle, i.e. crossing the North Pole. This represents the 0° and 180° meridians, which meet at the North Pole as shown in figure given below:
To draw a longitude, imagine that you are on the North Pole, i.e. at the centre of the circle as shown in Figure given above.
Observe now that the relative directions of east and west would reverse in this case and east would be towards your left while west would be towards your right.
Now, draw 45° E and W as shown in Figure given below:
For this, place your protractor along the vertical line, coinciding with the 0° and 180° meridians and then measure 45° on both the sides, which will denote 45° . E meridian and 45° W meridian on your left and right, respectively.
The diagram will represent the appearance of the earth if we look at it from directly above the North Pole.
Q1.What is the utility of scale in a map? Answer: A map scale provides the relationship between the map and the whole or a part of the earth’s surface shown on it. We can also express this relationship as a ratio of distances between two points on the map and the corresponding distance between the same two points on the ground.
Scale of a map determines whether it can reflect minor details on it. For example to locate Palam Vihar in Gurgaon if we locate it on world map, it will be of no use. It is better to use a map of Gurgaon to locate Palam Vihar on it.
On the basis of scale, maps are classified into small-scale maps and large-scale maps.
Q2.What factors must be kept in mind while selecting scale? Answer: We must consider following aspects while selecting scale:
Purpose of map: If map is being drawn to study the minor details then we should make use of large scale maps and if it is to show physical features or large areas, we can use small scale maps as well. For example scale of a map of a house will be larger than map of a country.
Space Available: Scale is also affected by availability of space for drawing maps.
Q3.What are limitations of representative fraction? Answer: There are many limitations of representative fraction method. These are as follows:
This method is only a fraction. It does not make use of any measurement system. Therefore it cannot be used to measure the direct distance between two places.
Whenever maps are changed using computers, these fractions get changed.
It is not easy to understand method for a layman.
Q4.In a scale statement it is mentioned that 1 inch represents four miles. Express it in representative fraction. Answer: 1 inch on map represents 4 miles on ground. Or 1 inch = 4 x 63360 ( 1 mile = 63360 inches) 1 inch = 2,53,440 inches. Therefore 1 inch on map represents a distance of 2,53,440 inches on ground. In other words, 1 unit on map represents 2,53,440 units on ground. Therefore Representative fraction
Q5.Convert Representative fraction 1:2,53,440 into a statement of scale (metric system). Answer: The given representative fraction can be converted into statement of scale in following steps: 1: 2,53,440 means that 1 unit on map represents 2,53,440 units on the ground. In other words, 1 cm will represent 2,53,440/1,00,000 km (because 1 km = 1,00,000 cm) Therefore, 1 cm = 2.5344 km In statement of scale form we can say that 1 cm represents 2.5344 km.
Long Answer Type Questions:
Q1.Construct a graphical scale for representative fraction 1:50,000 in which distance is given in furlongs and miles. Answer: For graphical scale, to know the length of the line we need to make following calculations. 1:50,000 means 1 unit on map represents 50,000 units on ground. In this way, 1 inch = 50,000 inches 6 inches = 50,000 x 6/63360 6 inches = 4.73 miles Since 4.73 miles is not an integer, therefore we take 5 as an integer on number line. Now we need to make following calculations to present number line as 5 miles. Since 6 inches = 4.73 miles Therefore 5 miles = 6 x 5/4.73 5 miles will be represented by 6.34 inches. We can make the graph by following steps: First of all draw a 6.34 inches line and divide it in 5 important parts. Except one part from the left, let us give all parts a distance of 1.268 inch. Now divide the first part in 4 equal parts and each part will be equal to 0.32 inch.
Q2.Construct a graphical scale for scale 1 inch = 1 mile and which can be read in furlongs and miles. Answer: For graphical scale, to know the length of the line we need to make following calculations. 1 inch = 1 mile Since 1 inch = 1 mile and therefore, 6 inches = 6 miles We can make the graph by following steps: First of all draw a 6 inches line and divide it in 6 important parts. Except one part from the left, let us give all parts a distance of one 1 inch. Now divide the first part in 4 equal parts and each part will be equal to 0.25 inch.
