Two planets have masses | Gravitation |JEE-Main 2020

JEE MAIN 2020

06-09-2020 S2

Question

Two planets have masses M and 16M and their radii are a and 2a, respectively. The separation between the centres of the planets is 10a. A body of mass m is fired from the surface of the larger planet towards the smaller planet along the line joining their centres. For the body to be able to reach at the surface of smaller planet, the minimum firing speed needed is

Select the correct option:

$\frac{3}{2} \sqrt{\frac{5 G M}{a}}$

$\sqrt{\frac{G M^2}{m a}}$

$2 \sqrt{\frac{G M}{a}}$

$4 \sqrt{\frac{G M}{a}}$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution