General Knowledge - Physics - Discussion

When the different tube of insufficient length then water may change its meniscus.

This is because capillary action depend on cross sectional area of the tube not the length and water have Concave meniscus.

It will rise something.

But not fully NoT rise in previous.

2tcos0 = rhdg as per this formula capillarity depends on both cross sectional area and height == (rh = constant).

If insufficient length capillary is used the water rise to its brim but does not over flow because of surface tension of water which provides a membrane behaviour.

Area decreases as it is thin, so height increases. Again small height given so it will overflow.

The water will rise but as soon as it reaches the opening of tube it will change its meniscus due to air pressure and will stop there. It won't overflow.

Because the change in the shape of capillary tube and the their change in length i.e.

                                 change in length
Longitudinal strain=----------------    
                                 original length

The surface tension is an interfacial force. The surface tension force pulls the liquid tangential to the wall of the capillary. When a capillary is dipped in water, it starts rising up due to pulling force from the solid-vapor interface. If the capillary has insufficient length, as the water rises it accelerates till the end of the capillary. When it reaches the edge of the capillary, water would gain some kinetic energy and due to inertia it slightly overshoots the edge of the tube. Then water surface bulges out due to which the tension at the solid-vapor interface turns downward which tries to pull the water column downward.

The liquid column will make some oscillations and finally after sometime the oscillations dampen out due to viscous effects. At steady state, the water column will fill the entire capillary and the radius of curvature of the meniscus will be just about adjusted such that the vertical component of surface tension force would balance the weight of water column.

This happens because the liquid rises up to the top end of the tube and then adjusts the radius of its curvature of its meniscus.

Meniscus means the curved upper surface of liquid in a glass tube.
For colourless liquids we consider upper meniscus whereas in case of colour liquids we consider lower meniscus.