Water is stored in a reservoir at an average vertical height of 350 m above the turbines of a hydroelectric power station.
During a 7.0 hour period, 1 .8 x 106 m3 of water flows down from the reservoir to the turbines'
(a) The density of water is 1000kg/m3'
For this 7.0 hour Period, calculate

ii) the gravitational potential energy transformed as the water flows to the turbines'

Can anyone answer this and tell me how to find the gravity in the equation (mgh) ?