Question

On any planet, the presence of atmosphere implies :
($v_{rms}=$ root mean square velocity of molecules, $v_e=$ escape velocity)

• A. $v_{rms}<<v_e$
• B. $v_{rms}>v_e$
• C. $v_{rms}=v_e$
• D. $v_{rms}=0$

Answer 1

Answer: (A)

$v_{rms}<<v_e$

Escape velocity $,v_e$ is the speed at which the sum of an object's kinetic energy and its gravitational potential energy is equal to zero.with escape velocity in a direction pointing away from the ground of a massive body, the object will move away from the body, slowing forever and approaching but never reaching zero speed.

$v_{rms}$ speed is the speed at which molecules move and should always be $<<v_e$ as they should not escape from atmosphere.

Option A is correct.