A dam is used to block the passage of a river and to generate electricity. Approximately 58.4 x 103 kg of water falls each second through a height of 20.1 m. If one half of the gravitational potential energy of the water were converted to electrical energy, how much power (in MW) would be generated?

Question

A dam is used to block the passage of a river and to generate electricity.  Approximately 58.4 x 103 kg of water falls each second through a height of 20.1 m.  If one half of the gravitational potential energy of the water were converted to electrical energy, how much power (in MW) would be generated?
 Can some one please help me with this problem? Thank you

bobpursley · Answer

power= PE rate*efficiency = 58.4kg/s *9.8m/s^2*20.1m*1/2