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Water rises to a height 'h' in a capillary tube. If the length of capillary tube above the surface of water is made less than 'h' then:

1. water rises upto the top of capillary tube and stays there without overflowing
2. water rises upto a point a little below the top and stays there
3. water does not rise at all
4. Water rises upto the top of capillary tube and then starts overflowing like fountain

Correct answer: water rises upto the top of capillary tube and stays there without overflowing

Solution

When the length of the capillary tube is less than the height 'h', water will rise to the top of the tube and stay there due to capillary action, but it will not overflow as the adhesive and cohesive forces balance out.

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