State the energy changes taking place when the water stored in the dam produces electric current on passing through electric generator.
Potential energy → Kinetic energy → Electrical energy
Kinetic energy → Electrical energy → Potential energy
Potential energy → Electrical energy → Kinetic energy
Electrical energy → Kinetic energy → Potential energy
(a) Name three types of substances in which an electric current can produce a chemical effect. (b) State some of the characteristics of chemical changes brought about by the chemical effect of electric current. (c) Why does an electric bulb glow when a current passes through it ?