Question
Mon February 27, 2012 By: Nevil Shah
 

What is the work done by the force of gravity in the following cases? 1. Satellite moving around the earth in a circular orbit 35000 km 2.A stone of mass 250 g is thrown up through a height of 2.5m.

Expert Reply
Tue February 28, 2012
1. case of satellite: work done will be 0, as the displacement here is occuring in perpendicular direction to the force applied ie gravity.
2. case 2:here also as the stone comes back tpo the earth, the displacement is 0. so the net work done by gravitational force will be 0. in moving the stone up the workdone will be exactly the same and opposite while  the stoneis coming  down.
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