When we press the bulb of a dropper with its nozzle kept in water, air in the dropper is seen to escape in the form of bubbles. Once we release the pressure on the bulb, water gets filled in the dropper. The rise of water in the dropper is due to :

Options

A. pressure of water.
B. gravity of the earth.
C. shape of rubber bulb
D. atmospheric pressure

Answer

D

Explanation

The rise of water in the dropper is due to atmospheric pressure. The rise of water in a dropper is due to atmospheric pressure. When all the air escapes from the nozzle, the atmospheric pressure, which is acting on the water, forces the water to fill the nozzle of the dropper.