The height of a mercury barometer is h when the atmospheric pressure is 100,000 Pa. At height h/5, what is the pressure?
The choices given are
The answer given is:
Pressure at height h/5 = (h-h/5) of Mercury = (4/5)*100,000 Pa = 80,000 Pa.
Why h-h/5? I think it should be (1/5)*100,000=20,000?
Then there is a note below the answer that says
The pressure of liquid is proportional to the depth of liquid.
I understand that but do not understand why it must be 4/5 of 100,000.
So at height 4h/5, the pressure is 20,000 Pa?