Capillarity and Capillary Action

IMPORTANT

Capillarity and Capillary Action: Overview

This Topic covers sub-topics such as Capillary Action, Application of Capillarity, Calculation of Capillary Rise, Capillarity and Capillary Tube and, Reason for Capillary Action

Important Questions on Capillarity and Capillary Action

MEDIUM
IMPORTANT

On dipping one end of a capillary in liquid and inclining the capillary at an angles 30o and 60​o with the vertical, the lengths of liquid columns in it are found to be l 1 and l 2 respectively. The ratio of l 1 and l 2 is

MEDIUM
IMPORTANT

On dipping one end of a capillary in liquid and inclining the capillary at an angles 300 and 600 with the vertical, the lengths of liquid columns in it are found to be l 1 and l 2 respectively. The ratio of l 1 and l 2 is

EASY
IMPORTANT

Water rises in a vertical capillary tube upto a height of 2.0 cm. If the tube is inclined at an angle of 60°with the vertical, then upto what length the water will rise in the tube

EASY
IMPORTANT

Water rises in a vertical capillary tube up to a height of 2.0 cm. If the tube is inclined at an angle of 60° with the vertical, then up to what length the water will rise in the tube?

HARD
IMPORTANT

An incompressible liquid is kept in a container having a weightless piston with a hole. A capillary tube of inner radius 0.1 mm is dipped vertically into the liquid through the airtight piston hole, as shown in the figure. The air in the container is isothermally compressed from its original volume V0 to 100101V0 with the movable piston. Considering air as an ideal gas, the height h of the liquid column in the capillary above the liquid level in cm is _____.

[Given: Surface tension of the liquid is 0.075 N m1, atmospheric pressure is 105 N m2, acceleration due to gravity g is 10 m s2, density of the liquid is 103 kg m3 and contact angle of capillary surface with the liquid is zero]

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EASY
IMPORTANT

A liquid of contact angle 60° rises in the capillary up to height h. If another capillary of same diameter is dipped in same liquid of contact angle 0° then rise will be

MEDIUM
IMPORTANT

Find the rise of water h in mm in the capillary as shown in figure. (Radius of capillary =2 mm, Angle of contact =0°, and surface tension of water =40 dyne/cmg=10 ms-2).
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MEDIUM
IMPORTANT

Liquid reaches an equilibrium as shown, in a capillary tube of internal radius r. If the surface tension of the liquid is T, the angle of contact θ and density of liquid ρ, then the pressure difference between P and Q is

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MEDIUM
IMPORTANT

In a U-shaped tube the radius of one limb is 2 mm and that of other limb is 4 mm. A liquid of surface tension 0.03 Nm-1, density 1500 kgm-3 and angle of contact zero is taken in the tube. The difference in the heights of the levels of the liquid in the two limbs is
(Acceleration due to gravity =10 ms-2)

EASY
IMPORTANT

Which of the following graphs represent the relation between capillary rise h and the radius r of the capillary?

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MEDIUM
IMPORTANT

The correct formula to determine surface tension by capillary rise method is

MEDIUM
IMPORTANT

Water rises to height H in a capillary of radius r and angle of contact is zero as shown in figure. The density and surface Tension of water is ρ and T respectively.
Acceleration due to gravity is g and atmospheric pressure is P0. Now, identical capillary as of (i) is bend in different forms as shown in the figure (ii), (iii) and (iv)

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MEDIUM
IMPORTANT

When water rises in a capillary tube of radius 'r' to height 'h', then its potential energy 'U1' if capillary tube of radius 2r is dipped in same water then potential energy of water is U2''. Then U1:U2 will be
 

MEDIUM
IMPORTANT

A capillary tube of radius 'r' is lowered into water whose surface tension is 'α' and density 'd'. The liquid rises up and settles to a certain height. Assume that the contact angle is zero. Choose the correct statement(s) for this entire process

MEDIUM
IMPORTANT

A small amount of water is poured from the top and the water surface assumes the profile as shown in the figure. Assume that water does not wet the vertical part of the tube. The angle of contact α is 120° and the surface tension of water is 0.070 Nm-1. The thickness h of the layer of water is nearest to (assume the thickness of the layer of water substantially smaller than the diameter of opening of tube, and g=10 ms-2 )

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HARD
IMPORTANT

In a capillary tube placed inside the liquid of density ( ρ )in a container, the rise of liquid is h. When block of density ' σ ' is placed on the liquid as shown in the figure, liquid in the tube is h'. If σ<ρ then

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HARD
IMPORTANT

Capillary tube with very thin walls is suspended vertically in a cup containing water. Before the capillary is suspended, the cup was balanced against weights on a beam balance. When capillary is dipped to a small distance in the water, water rises in the capillary. Water completely wets the capillary walls. To restore the balance, we have to decrease the load on the other scales by 0.14 g. If the surface tension of water is 0.07 N m-1, determine the radius r (in mm) of the capillary.

MEDIUM
IMPORTANT

In a capillary tube of length 20 cm and bore diameter 1 mm, a very thin glass rod of diameter 0.5 mm is coaxially arranged. The arrangement is dipped in water for which angle of contact with glass is 0°. What is the difference in length of capillary raise if the tube is vertical in a case and is at 30° to the horizontal in other? Express the magnitude in cm. Surface tension of water is 0.075 N m-1

EASY
IMPORTANT

Capillary action is important for moving _____ around.