The escape velocity on the surface of the earth is 11.2 `kms^(-1)`. If mass and radius of a planet is 4 and 2 tims respectively than that of the earth, what is the escape velocity from the planet?

Options

A. 15.5 `km s^(-1)`
B. 55.5 `km s^(-1)`
C. 11.2 `km s^(-1)`
D. 22.4 `km s^(-1)`

Explanation

Escape velocity `V=R sqrt(8/3) pi Gp`
`rarr v prop R`
`therefore (v_(1))/(v_(2))=(R_(1))/(R_(2))`
or `(11.2)/(V_(2))=(R )/(2R) rarr V_(2)=22.4 kms^(-1)`