contestada

The rate of change of atmospheric pressure P with respect to altitude h is proportional to P, provided that the temperature is constant. At a specific temperature the pressure is 102.1 kPa at sea level and 87.8 kPa at h = 1,000 m. (Round your answers to one decimal place.) (a) What is the pressure at an altitude of 4500 m? kPa (b) What is the pressure at the top of a mountain that is 6165 m high?

Respuesta :

(a) 37.8 kPa

First of all, we need to find the rate of change of pressure per meter.

We know that:

at h = 0 m, the pressure is 102.1 kPa

at h = 1,000 m, the pressure is 87.8 kPa

So, the rate of change of pressure is

[tex]m=\frac{\Delta p}{\Delta h}=\frac{87.8 kPa-102.1 kPa}{1000 m-0 m}=-0.0143 kPa/m[/tex]

And so now we can calculate the pressure at any altitude by using the equation:

[tex]p(h) = p_0 + m h[/tex]

where

[tex]p_0 = 102.1 kPa[/tex] is the pressure at sea level

m is the rate of change of pressure

h is the altitude

Substituting h = 4500 m, we find

[tex]p=102.1 kPa + (-0.0143 kPa/m)(4500 m)=37.8 kPa[/tex]

(b) 13.9 kPa

As before, we can calculate the pressure at the top of the mountain by using the equation:

[tex]p(h) = p_0 + m h[/tex]

where

[tex]p_0 = 102.1 kPa[/tex] is the pressure at sea level

m is the rate of change of pressure

h is the altitude

Substituting this time h = 6165 m, we find

[tex]p=102.1 kPa + (-0.0143 kPa/m)(6165 m)=13.9 kPa[/tex]