A small amount of air is introduced into the vacuum above the mercury in a mercury barometer tube. The mercury level goes down because the air molecules
A
heat the mercury and make it expand
B
increase the pressure above the mercury.
C
cool the mercury and make it contract.
D
decrease the pressure above the mercury
Verified Correct Answer: B.
Physical Principles & Numerical Solution
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #58848)