No work is done on the earth revolving around it in a perfectly circular orbit. The earth revolves around the sun due to the 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 center 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
W=Fd cos 90
I don’t understand this website. Very cool, but why is there no “about” section?