Thread: Help me!

What is the fractional decrease in pressure when a barometer is raised 35 m to the top of a building? (Assume that the density of air is constant over that distance.)

Originally Posted by babygirl

What is the fractional decrease in pressure when a barometer is raised 35 m to the top of a building? (Assume that the density of air is constant over that distance.)

There is insufficient information in this problem to solve it.

If this was my problem I would look up in my text book or do a google search
for the altitude dependence of air pressure (giving priority to my text book
or what I have been told by my teacher).

There I might find air pressure drops by about 1 part in 1000 for every 8m
increase in altitude, for altitudes of less than a few hundred metres.

Alternatively you might find that the half height of the atmosphere for air
pressure is ~5000m

We really need to know what you are supposed to know about atmosheric
pressure before we can help you with this question.

RonL

RonL

Originally Posted by babygirl

What is the fractional decrease in pressure when a barometer is raised 35 m to the top of a building? (Assume that the density of air is constant over that distance.)

As CaptainBlack mentioned, I'm not sure of what you are using for your constants, but in general:


so the fractional decrease would be
.

(I'm presuming P is at sea level.)

-Dan