Question

A dam is used to block the passage of a river and to generate electricity. Approximately 5.73 × 104 kg of water fall each second through a height of 19.6 m. If 85 % of the gravitational potential energy of the water were converted to electrical energy, how much power would be generated?

Answer 1

Answer:

9.36 MW

Explanation:

Let g = 9.81 m/s2. Then the gravitational energy of that much water at a height of 19.6 m is as following

$E_P = mgh = 5.73*10^4*9.81*19.6 = 11017414.8 J$ per second or 11017414.8 W

If only 85% of this energy is converted to electrical energy then the power generated would be

11017414.8 * 85% = 9364802.58 W or 9.36 MW