TS EAMCET 7 May 2024 Shift 1 Solved Paper

A uniform narrow tube of length one metre with one end closed contains 25 cm long mercury thread, which traps a column of air at the closed end. When the tube is held vertically with the open end up, the length of the air column near the closed end is 21 cm and when the tube is held horizontally, the length of the air column near the closed end is ' L '. If the atmospheric pressure is equal to the pressure of 75 cm of mercury, then L is