P. 4805. A chain of length 30 m and of mass 40 kg is pulled up to a balcony at a height of 15, such that originally one end of the chain is already at the balcony. One half of the chain is hanging vertically and the other half lies on the ground in a small pile. How much work is done while the chain is pulled up?
Deadline expired on 10 March 2016.