- Home
- Standard 11
- Physics
7.Gravitation
medium
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
A
$1.99 \times {10^{30}}\,kg$
B
$7.56 \times {10^{22}}\,kg$
C
$5.98 \times {10^{24}}\,kg$
D
$7.65 \times {10^{22}}\,kg$
Solution
(d) ${g_m} = \frac{{G{M_m}}}{{R_m^2}}$ 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 $G = 6.67 \times {10^{ – 11}}N{\rm{ – }}{m^2}/k{g^2}$
We get ${M_m} = 7.65 \times {10^{22}}kg$
Standard 11
Physics