Question

if mass of a Planet 8 times that of the earth and its radius is twice the radius of the earth what will be the escape velocity of planet escape velocity of this for the earth is 11.2 km/s​

Answer 1

Escape velocity

$v_{e} = \sqrt{ \frac{2GM}{r} }$

Let mass of Earth be m and other planet be M

so , 8m = M

Radius of earth be r and other planet be R

so , 2r = R

Escape velocity of other planet ,

$= \sqrt{ \frac{2GM}{R} } \\ \\ = \sqrt{ \frac{2 \times G \times 8m}{2r} } \\ \\ = 2 \sqrt{ \frac{2Gm}{r} } \\ \\ = 2 v_{e}$