NTA Abhyas JEE Main2020ChemistryStates of MatterPractice
An air column closed in a tube sealed at one end by a H g column having height h . When the tube is placed with open end down, the height of the air column is l 1 . If the tube is turned so that its open end is at the top, the height of the air column is l 2 . What is the atmospheric pressure P 0 -
Options
- AP 0 = h l 1 + l 2 l 2 - l 1 c m o f H g
- BP 0 = h l 1 - l 2 l 1 + l 2 c m o f H g
- C76 c m o f H g
- DP 0 = h l 1 + l 2 l 1 - l 2 c m o f H g .
Correct answer
D. P 0 = h l 1 + l 2 l 1 - l 2 c m o f H g .
Step-by-step solution
Let P 0 be the value at atmospheric pressure In case I: P g a s + h c m o f H g = P 0 c m o f H g In case ii P g a s = P 0 c m o f H g + h c m o f H g By applying Boyle's law between I & I I P 0 – h × l 1 = P 0 + h × l 2 or P 0 l 1 - h l 1 = P 0 l 2 + h l 2 or P 0 l 1 - l 2 = h l 1 + l 2 or P 0 = h l 1 + l 2 l 1 - l 2