(N/A) The electricity generated by using the energy of flowing water is called hydroelectricity.
The basic principle of the generation of hydroelectricity is as follows:
$1$. The water flowing in a river is collected by constructing a high-rise dam $D$ (See Fig.). This water,which has been stored at a high altitude,possesses a significant amount of potential energy.
$2$. The water stored in the high-rise dam is allowed to fall onto a water-turbine $G$ located near the base of the dam.
$3$. When the fast-moving water falls on the blades of the turbine,the kinetic energy of the water rotates the turbine rapidly.
$4$. The shaft of the turbine is connected to the coil of an electricity generator or dynamo. Consequently,when the water-turbine rotates rapidly,the generator coil fixed on its shaft also rotates rapidly,thereby producing electricity.