Gravitation Question 30
Question: Weight of 1 kg becomes 1/6 on moon. If radius of moon is $ [1.768\times 10^{6},m] $ , then the mass of moon will be[RPET 1997]
Options:
A) $ [1.99\times 10^{30},kg] $
B) $ [7.56\times 10^{22},kg] $
C) $ [5.98\times 10^{24},kg] $
D) $ [7.65\times 10^{22},kg] $
Show Answer
Answer:
Correct Answer: D
Solution:
$ [g_{m}=\frac{GM_{m}}{R_{m}^{2}}] $
and $ [g_{m}=\frac{g_{e}}{6}=\frac{9.8}{6}\ m/s^{2}] $ $ [=1.63\ m/s^{2}] $
Substituting $ [R_{m}=1.768\times 10^{6}m,] $ $ [g_{m}=1.63\ m/s^{2}] $
and $ [G=6.67\times {{10}^{-11}}N\text{-}m^{2}/kg^{2}] $
We get $ [M_{m}=7.65\times 10^{22}kg] $
