9781422275993

A n electric current is defined as the amount of charge flowing through a wire at a given time. This form of flowing energy is known as cur- rent electricity. There is just one difference between static electricity and current electricity. Static electricity occurs due to the collection of charges whereas current electricity exists due to the flow of charges. Electricity is measured in amperes and it is denoted by the symbol A. Electric Current

Heating Effect of Electric Current When an electric current is passed through a con- ductor, there is a resistance in the flow of electric current and this generates heat. This heating prop- erty of electric current is used in appliances like electric immersion water heaters, electric irons, etc. All of these have a heating element in them, which is generally made of specific alloys like nichrome, manganin , constantan , etc. A good heating ele- ment has high resistivity and high melting point. An electric fuse is an example of the application of the heating effect of an electric current.

Converting heat to electricity

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SCIENCE & TECHNOLOGY