a pilot records the atmospheric pressure outside his plane as 63cm of Hg while a...

PHYSICS
WAEC 1998

a pilot records the atmospheric pressure outside his plane as 63cm of Hg while a ground observer records a reading of 75cm of Hg with his barometer. Assuming that the density of air is constant, calculate the height of the plane above the ground. (take the relative densities of air and mecury as 0.00136 and 13.6 respectively)

  • A. 120m
  • B. 138m
  • C. 274m
  • D. 1200m

Correct Answer: D. 1200m

Explanation

pressure change for air = pressure change for mercury

hpg = Hpg

h x 0.00136 x g = (75 - 63) x 13.6 x g

h = \(\frac{12 \times 13.6}{0.00136}\)

= 120,000cm

= 1,200m



Post an Explanation Or Report an Error
If you see any wrong question or answer, please leave a comment below and we'll take a look. If you doubt why the selected answer is correct or need additional more details? Please drop a comment or Contact us directly. Your email address will not be published. Required fields are marked *
Add Math
Don't want to keep filling in name and email whenever you make a contribution? Register or login to make contributing easier.