To make an electromagnet, insulated copper wire is wound around a rod of soft iron. The ends of the wire are connected to an electric cell through a key . As the wise is insulated there is on electrical contact between the wire and the rod. If the wire is bare i.e. Not insulated, there will be electrical contact between the wire and the rod and consequently between the adjacent turns of the wire . This will reduce the electrical resistance in the circuit significantly. He the key is closed under such condition, the wise will carry large current and become very got. In a short time practically all the electrical energy in the cell will be converted into heat. To avoid this the copper wise used in an electromagnet is insulated.
No comments:
Post a Comment