Question

Escape velocity on earth is $11.2$ km/s. What would be the escape velocity on planet whose mass is $1000$ times and radius is $10$ times that of earth :

• A. $112$ km/s
• B. $11.2$ km/s
• C. $1.12$ km/s
• D. $3.7$ km/s

Answer 1

The correct option is A $112$ km/s

Escaping velocity $V_e=\sqrt{\frac{2GM}{R}}$

$\frac{v_p}{v_e}=\sqrt{\frac{M_p}{M_e}\frac{R_e}{R_p}}=\sqrt{\left(1000\right)\times (\frac{1}{10})}=10$
$v_p=10\times 11.2=112km/s$