# Does the sun do any work on earth?

No work is done on the earth revolving around it in perfectly circular orbit.The earth revolves around the sun due to gravitational force of attraction between the sun and the earth.This gravitational force provides centripetal force to the earth to revolve around the sun.Since centripetal force is always directed towards the centre of the orbit.This centripetal force is always perpendicular to the linear displacement ‘d’ which is tangent to the circle so:

W=**F.d** =Fd cosθ

Since θ=90

W=Fd cos 90

W=0