The percentage by which the moon should move faster, so that it escapes from the gravitational field of the earth is:

Options

A. `41.4%`
B. `20%`
C. `50%`
D. `64.3%`

Answer

A

Explanation

For the moon, `v_(e)=sqrt(2)v_(0)`
`therefore v_(e)-v_(0)=sqrt(2)v_(0)-v_(0)=v_(0)(sqrt(2)-1)`
`=v_(0)(1.414-1)=0.414 v_(0)`
`therefore` To escape from the gravitational field of the earth, the moon should move faster by 41.4 %.