Planet A in a distant stellar system moves round its star in a nearly circular orbit…

PHYSICS · Subjective · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Planet A in a distant stellar system moves round its star in a nearly circular orbit of radius

1.50\times10^{11}\,\text{m}

and completes one revolution in

300\,\text{days}

. A second planet B in the same system takes

800\,\text{days}

to complete one revolution. (i) Determine the orbital radius of planet B. (ii) Express the result of part (i) in astronomical units

(1\,\text{AU}=1.496\times10^{11}\,\text{m})