The height at which the atmosphere ceases to exist is about 80km. If the atmospheric pressure on the ground level is 760mmHg, the pressure at a height of 20km above the ground level is
(ρm = 13.6g/cm(^3) ρ = 0.00013g/cm(^3) )
-
A.
380mmHg -
B.
570mmHg -
C.
190mmHg -
D.
480mmHg
Correct Answer: Option B
Explanation
ρ(_m)h(_m) = ρ(_a)h(_a)
13.6(760 – p) × 10(^{-3}) = 13 × 10(^{-5})(20 × 10(^3))
| 760 | – | p | = | 13 × 10(^{-5}) × 20 × 10(^{3})
13.6 × 10(^{-3}) |
= | 19.12 | × | 10(^{1}) |
760 – p = 191.2
p = 760 – 191.2 ≈ 570mmHg
There is an explanation video available below.