Rankers Physics
Topic: Gravitation
Subtopic: Gravitational Potential Energy

For a planet having mass equal to mass of the earth but radius is one fourth of radius of the earth, Then escape velocity for this planet will be:

(2000)

$11.2\text{ km/s}$
$22.4\text{ km/s}$
$5.6\text{ km/s}$
$44.8\text{ km/s}$

Solution:

Escape velocity is given by $v_e = \sqrt{\frac{2GM}{R}}$. Since mass is constant and radius becomes one-fourth, $v_e$ increases by a factor of $\sqrt{4} = 2$. Thus, $v_p = 2 \times 11.2\text{ km/s} = 22.4\text{ km/s}$. Option B is correct.

Leave a Reply

Your email address will not be published. Required fields are marked *