Mass of moon is `7.34 xx 10^(22)` kg . If the acceleration due to gravity on the moon is `1/4 m//s^(2)` , the radius of the moon is `(G = 6.667 xx 10^(-11) Nm^(2)//kg^(2))`

Options

A. `0.56 xx 10^(4) m `
B. ` 1. 87 xx 10^(6) m `
C. ` 1. 92 xx 10^(6) m `
D. ` 1.01 xx 10^(8) m `

Answer

B

Explanation

We know g `= (GM)/( R^(2)) :. R = sqrt((GM)/( g)) = sqrt((6 . 67 xx 10^(-11) xx 7 . 34 xx 10^(22))/(1. 4)) = 1. 87 xx 10^(6) m `