Surface Tension Multiple Choice Questions and Answers

21. The surface tension of a liquid is T. the increase in its surface energy on increasing the surface area by A is

1. AT^-1
2. AT
3. A²T
4. A²T²

22. The surface tension of water at 250C is

1. 90.0 dynes/cm
2. 45.63 dynes/cm
3. 82.5 dynes/cm
4. 72.14 dynes/cm

23. The unit of surface tension in the CGS system is

1. N/m
2. Kg/cm
3. Dynes/cm
4. Dynes/m

24. What is the main cause of capillarity?

1. difference in weight of fluids
2. pressure difference
3. temperature difference
4. velocity gradient

25. What is the property of a liquid due to which its free surface tries to have minimum surface area?

1. Viscosity
2. Buoyancy
3. Surface Tension
4. Rigidity

26. What is the shape of meniscus when angle of contact is greater than 90 degree?

1. Concave
2. Convex
3. Plane
4. None of the above

27. What will be the change in the height of water in a capillary tube in stationary condition on earth if the same tube is taken in a lift going downward with acceleration?

1. height increases
2. height decreases
3. Remains same
4. can decrease or increase

28. When impurity is added to a liquid, its surface tension

1. decreases
2. first decreases and then
3. increases increases
4. remains same

29. When will the height of water in capillary tube be minimum?

1. When water temperature is 0 degree C
2. When water temperature is 4 degree C
3. When water temperature is -4 degree C
4. None of the above

30. Which is correct about the height of a capillary column of a liquid, at a particular temperature, as per Jurin’s law?

1. equal to the diameter of the tube
2. directly proportional to the diameter of the tube
3. inversely proportional to the diameter of the tube
4. half of the diameter of the tube