Question

If a new planet is discovered rotating around sun with the orbital radius double that of the earth, then what will be its time period?
(in earth's days)

• A. 1032
• B. 1023
• C. 1024
• D. 1043

Answer 1

The correct option is A 1032

By Kepler's third law, $T^2\propto R^3$
$\therefore {\left(\frac{T_2}{365days}\right)}^2={\left(\frac{2r}{r}\right)}^3$
$T_2=365\times 2\sqrt{2}=1032days$