The temperature, at which the root mean square
velocity of hydrogen molecules equals their
escape velocity from the earth, is closest to :
[Boltzmann Constant k
B
= 1.38 × 10
–23
J/K
Avogadro Number N
A
= 6.02 × 10
26
/kg
Radius of Earth : 6.4 × 10
6
m
Gravitational acceleration on Earth = 10ms
–2
]