Question

The radius of Jupiter is approximately 11 times larger than the earth. Jupiter has a mass 316 times that of earth. What is the approximate escape velocity of Jupiter compared to earth?

(a) 100 times greater

(b) 12 times greater

(c) 5 times greater

(d) Equal to that of the earth

I got this question during a job interview.

My question comes from Gravitation in division Gravitation of Physics – Class 11

Answer 1

Correct choice is (c) 5 times greater

For explanation I would say: M = Mass of the earth

R = Radius of the earth

v = Escape velocity of the earth

We know;

v = [(2 x G x M)/R] ^1/2

M’ = Mass of the Jupiter

R’ = Radius of the Jupiter

v’ = Escape velocity of the Jupiter

M’ = 316M

R’ = 11R

v’ = [(2 x G x M’)/R’] ^½

 = [(2 x G x 316M)/11R] ^½

 = 5.6 x [(2 x G x M)/R] ^1/2

 = 5.6 x v.