Question

What isthe work done by the force of gravity on a satellite moving round theearth? Justify your answer.

Answer 1

Workis done whenever the given two conditionsare satisfied:

(i) Aforce acts on the body.

(ii) There is a displacement of the body by the application of forcein or opposite to the direction of force.

Ifthe direction of force is perpendicular todisplacement, then the work done is zero.

Whena satellite moves around the Earth, then the direction of force ofgravity on the satellite is perpendicular to its displacement. Hence,the work done on the satellite by the Earthis zero.