For moon, its mass is 1/81 of earth mass and its diameter is 1/3.7 of earth dia. If acceleration due to gravity at earth surface is 9.8 `m//s^2` then at moon its value is :

Options

A. 2.86 `m//s^2`
B. 1.65 `m//s^2`
C. 8.65 `m//s^2`
D. 5.16 `m//s^2`

Answer

B

Explanation

`g=(GM)/(R^2) " or " gpropM/R^2`
`g_M=(M_M)/(M_E)xx((R_E)/(R_M))^2xxg_E`
`=1/81xx(3.7)^2xx9.8=9.8/6=1.65 m//s^2`