The most common gas in the atmosphere of our solar system is ______

Helium

Nitrogen

Hydrogen

Carbon dioxide

Correct Answer : Helium

Explanation : Helium is the most common gas in the atmosphere of our solar system. It comprises of a significant portion in the atmosphere of Sun, Mercury, Moon, Jupiter, Saturn, Uranus and Neptune. The second common gas in the solar system is Hydrogen gas, followed by Nitrogen and Carbon dioxide gas.

Recently Updated in Spaceflight Mechanics Questions

Using Toussaint's formula, what is the temperature of air at a geopotential altitude of 4 km?

231 K

250 K

255 K

262 K

Correct Answer : Option (D) : 262 K

Explanation : Toussaint’s formula is given by T = 15 – 0.0065h
Where, T is the temperature in Celsius and h is the geopotential altitude in metres.
Therefore, T = 15 – 0.0065*(4000)
= – 11°C
= -11 + 273 K
= 262 K

U.S. Air Force defines the ____________ as the boundary between earth's atmosphere and space.

Karman line

Van Allen belt

Beginning of exosphere

Beginning of mesosphere

Correct Answer : Option (A) : Karman line

Explanation : The beginning of space is officially denoted at an altitude of 100 km which is also known as the Kármán line. After this line the aerodynamic effects are minimal. Cold gas thrusters are used to correct orientation after this line as aerodynamic control surfaces are useless.

What is the temperature of air if the pressure and density are 629.66 lb/ft² and 0.9408 x 10^-3 slug/ft³. Given specific gas constant is 1716 lb.ft/slug.⁰R.

125 ⁰R

225 ⁰R

250 ⁰R

390 ⁰R

Correct Answer : Option (D) : 390 ⁰R

Explaination : Given,
Pressure (p) = 629.66 lb/ft²
Density (ρ) = 0.9408 x 10^-3 slug/ft³
Specific gas constant (R) = 1716 lb.ft/slug.⁰R
Using equation of state,
Temperature, T = p/(ρR)
= 629.66/(0.9408*10^-3*1716)
= 390 ⁰R