A coal-fired power station generates electricity at night when it is not needed.
Some of this energy is stored by pumping water up to a mountain lake. When there is high
demand for electricity, the water is allowed to flow back through turbines to generate electricity.
On one occasion, 2.05 x 108 kg of water iS pumped up through a vertical height of 500 m.
(1)
Calculate the weight of the water.
