JEE Main Rank Booster 2021
This course will help student to be better prepared and study in the right direction for JEE Main..
₹ 13999/-
₹ 9999/-
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The hole at the top is made so that there is a pressure at the top of the oil by the air and the oil can come out through the bottom hole. If the top hole is not there the oil cannot come out of the bottom hole since the pressure in the hole at the bottom is more than the oil inside.