Originally Posted by **angelica** I dont understand. can u explain how to get to that?
Thanks |

The work done force times distance. In order to raise a bucket of mass m you have to exert a force to the bucket which is equal to the weight of the bucket. The distance is the height you have to raise the bucket. Let h be depth of well. let F = W = mg = weight of bucket. Then the work = force * distance = (Mg)(h) = mgh. But this is simply the increase in the potential energy of the bucket!