Question

the atmosphere of town A is 50cmHg while at sealvel the pressure is 76cmHg.Calculate the altitude of the town given that the density of air is1.25 kg/m3

Answer 1

Correct option is

B

2.5 km

Pressure differences between sea level and the top of hill

△p=(h

1

−h

2

)×p

Hg

×g

=(75−50)×10

−2

×p

Hg

×g ...(i)

and pressure difference due to h metre of air

△p=h×p

air

×g ...(ii)

By equating Eqs. (i) and (ii)

h×p

air

×g

=(75−50)×10

−2

×p

Hg

×p

p=25×10

−2

(

p

air

p

Hg

)

=25×10

−2

×10

4

=2500m

∴ Height of hill = 2.5 km