Question

The basic barometer can be used to measure the height of a building. If the barometric readings at the top and the bottom of a buikding are 730 and 755 mmHg, respectively, determine the height of the building. Assume an average air density of 1.25 kg/m^3. Provide with a simple sketch and graph it (hydrostatic pressure).

Answer 1

`h = 269.6 m`

Step-by-step explanation:

Pressure at the bottom of the building and at the top of the building must be related as

`P_(top) = P_(bottom) - \rho g h`

`P_(top) = 730 mm Hg`

`P_(bottom) = 755 mm Hg`

now we will have

`(755 * 10^(-3))(13.6 * 10^3)(9.81) = P_(bottom)`

`P_(bottom) = 1.007 * 10^5 Pa`

`P_(top) = (730* 10^(-3))(13.6 * 10^3)(9.81)`

`P_(top) = 0.974 * 10^5`

now we have

`(1.007 - 0.974)* 10^5 = 1.25 (9.81) h`

`h = 269.6 m`