A planet $\left(P_1\right)$ is moving around the star of mass $2 M$ in the orbit of radius $R$. Another planet $\left(P_2\right)$ is moving around another star of mass 4 M in a orbit of radius 2 R . Ratio of time periods of revolution of $\mathrm{P}_2$ and $P_1$ isA planet $\left(P_1\right)$ is moving around the star of mass $2 M$ in the orbit of radius $R$. Another planet $\left(P_2\right)$ is moving around another star of mass 4 M in a orbit of radius 2 R . Ratio of time periods of revolution of $\mathrm{P}_2$ and $P_1$ is