Back to GRAVITATION

JEE PHYSICS MCQ: GRAVITATION

1 Easy

1 of 1

Application +4 | -1

A ring of mass

m_1

and radius

R

is fixed in space at some location. An external agent brings a point mass

m_2

from infinity to centre of the ring. Work done by the external agent will be

View answer and explanation

Correct option: A

-\frac{G m_1 m_2}{R}

Option A (

-\frac{G m_1 m_2}{R}

) is correct because the work done by the external agent is equal to the change in potential energy, which is negative in this case.

More Questions from GRAVITATION

Practice All Chapter MCQs →

The escape velocity for a body projected vertically upwards from the surface of the earth is

11.2\mathrm{\;\;km}{\mathrm{s}^{ - 1}}

. If the body is projected in a direction making an angle of

{45^0}

with the vertical, the escape velocity will be The escape velocity of a body projected from the surface of earth is

v_e

. If the body is projected at an angle

\theta

to the horizontal surface of earth, then the escape velocity would be If different planets have the same density but different radii, then the acceleration due to gravity on the surface of the planet is related to the radius (R) of the planet as Which of the following statement is absolutely correct about mass Statement I: An astronaut in a satellite feels weightlessness:

Statement II: As observed by another astronaut's in the same satellite, force of gravity and centrifugal force balance each other. An iron ball and a wooden ball of the same radius are released from a height 'h' in vacuum. The time taken by both of them to reach the ground is