The temperature, at which the root mean square velocity of hydrogen molecules equals their escape velocity from the earth, is closest to :
[Boltzmann Constant kB=1.38×10−23 J/K
Avogadro Number NA=6.02×1026/kg
Radius of Earth : 6.4×106 m
Gravitational acceleration on Earth = 10 ms−2 ]
(1) 800 K
(2) 3×105 K
(3) 104 K
(4) 650 K