B. A current in charges change direction
Explanation: an electric current that reverses its direction many times a second at regular intervals, typically used in power supplies.
Is by turning a few seconds before
The exothermic process is a process or reaction that involves a release of energy from the system to its surroundings in various forms usually through heat, light, electricity or sound. In the four given choices, when melting a copper, you try to immerse the metal in heaping coals of fire. The metal will absorb the thermal energy coming from the coal, thus, once you retrieve the metal back, light will be emitted from it as well as heat.
Therefore, the answer is B. MELTING OF COPPER
Earth is so hot inside that magma erupts and flies out. LOL hope this helps.
