In This Post we are  providing Chapter-10 Mechanical Properties of Fluids NCERT MCQ for Class 11 Physics which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS  can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.

NCERT MCQ ON MECHANICAL PROPERTIES OF FLUIDS

Question 1.
A number of small drops of mercury coalesce adiabatically to form a single drop. The temperature of drop
(a) Increases
(b) Is infinite
(c) Remains unchanged
(d) May decrease or increase depending upon size

Answer: (d) May decrease or increase depending upon size

Question 2.
Surface tension of a soap solution is 1.9 × 10^-2N/m. work done in blowing a bubble of 2.0 cm diameter will be
(a) 7.6 × 10^-6 p J
(b) 15.2 × 10^-6 p J
(c) 1.9 × 10^-6 p J
(d) 1 × 10^-4 p J

Answer: (b) 15.2 × 10^-6 p J

Question 3.
Plants get water through the roots because of
(a) Capillarity
(b) Viscosity
(c) Gravity
(d) Elasticity

Answer: (a) Capillarity

Question 4.
Choose the wrong statement from the following.
(a) Small droplets of a liquid are spherical due to surface tension
(b) Oil rises through the wick due to capillarity
(c) In drinking the cold drinks through a straw, we use the phenomenon of capillarity
(d) Gum is used to stick two surfaces. In this process we use the property of Adhesion

Answer: (c) In drinking the cold drinks through a straw, we use the phenomenon of capillarity

Question 5.
The height of a liquid in a fine capillary tube
(a) Increases with an increase in the density of a liquid
(b) Decreases with a decrease in the diameter of the tube
(c) Decreases with an increase in the surface tension
(d) Increases as the effective value of acceleration due to gravity is decreased

Answer: (d) Increases as the effective value of acceleration due to gravity is decreased

Question 6.
At critical temperature, the surface tension of a liquid
(a) Is zero
(b) Is infinity
(c) Is the same as that at any other temperature
(d) Can not be determined

Answer: (a) Is zero

Question 7.
A capillary tube when immersed vertically in a liquid records a rise of 3 cm. if the tube is immersed in the liquid at an angle of 60° with the vertical, then length of the liquid column along the tube will be
(a) 2 cm
(b) 3 cm
(c) 6 cm
(d) 9 cm

Answer: (c) 6 cm

Question 8.
When the angle of contact between a solid and a liquid is 90°, then
(a) Cohesive force > Adhesive force
(b) Cohesive force < Adhesive force
(c) Cohesive force = Adhesive force
(d) Cohesive force >> Adhesive force

Answer: (c) Cohesive force = Adhesive force

Question 9.
Water rises up to a height of 5 cm in a capillary tube of radius 2 mm. what is the radius of the radius of the capillary tube if the water rises up to a height of 10 cm in another capillary?
(a) 4 mm
(b) 1 mm
(c) 3 mm
(d) 1 cm

Answer: (b) 1 mm

Question 10.
If the surface of a liquid is plane, then the angle of contact of the liquid with the walls of container is
(a) Acute angle
(b) Obtuse angle
(c) 90°
(d) 0°

Answer: (d) 0°

Question 11.
Two soap bubbles have radii in the ratio of 4 : 3. What is the ratio of work done to below these bubbles?
(a) 4 : 3
(b) 16 : 9
(c) 09 : 16
(d) 3 : 4

Answer: (b) 16 : 9

Question 12.
The height of water in a capillary tube of radius 2 cm is 4 cm. what should be the radius of capillary, if the water rises to 8 cm in tube?
(a) 1 cm
(b) 0.1 cm
(c) 2 cm
(d) 4 cm

Answer: (a) 1 cm

Question 13.
Water rises up to a height of 4 cm, in a capillary tube immersed vertically in water. What will be the length of water column in the capillary tube, if the tube is immersed in water, at an angle of 60° with the vertical?
(a) 4 cm
(b) 6 cm
(c) 8 cm
(d) 2 cm

Answer: (c) 8 cm

Question 14.
The surface of water in contact with glass wall is
(a) Plane
(b) concave
(c) convex
(d) Both b and c

Answer: (b) concave

Question 15.
Pressure inside two soap bubbles is 1.01 and 1.02 atmospheres. ratio between their volume is
(a) 102 : 101
(b) (102)3 : (101)3
(c) 8 : 1
(d) 2 : 1

Answer: (c) 8 : 1

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