First slide

Universal law of gravitation

Question

When a satellite is orbitting round a planet in circular orbit, workdone by the gravitational force acting on the satellite is

Easy

A

zero on completing one revolution only
B

zero always
C

infinite
D

negative

Solution

Gravitational force $\large (\overrightarrow {F_g})$ of attraction of a planet on a satellite moving in circular orbit around the planet is radially inward and the direction of velocity $\large (\overrightarrow {V})$ of the satellite is along the tangent. So rate of work done on the satellite = $\large \overrightarrow {F_g}.\overrightarrow V$
= F_g V cos 90⁰ = 0
Hence option - (2) is right.

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App