Question

Moon is revolving round the earth as well as it is rotating about its own axis. The ratio of its angular momentum in two cases will be (orbital radius of moon $=3.82\times {10}^{8}m$ and radius of moon $=1.74\times {10}^{6}m$):

• A. $1.2\times {10}^{5/4}$
• B. $1.2\times {10}^{5/3}$
• C. $1.22\times {10}^{5/2}$
• D. $1.2\times {10}^5$

Answer 1

The correct option is D $1.2\times {10}^5$

The ratio is calculated as $\frac{M{R}_o^2}{\frac{2}{5}M{R}^2}=\frac{(3.82\times {10}^8{)}^2}{\frac{2}{5}(1.74\times {10}^6{)}^2})=1.2\times {10}^5$