Providing Heat
Electrons flow more easily through certain types of metals. Thicker wires also provide less resistance to electron flow than thinner wires. By placing a very thin wire (or a metal with relatively high resistance to electron flow) in a circuit, electrical energy can be converted into heat energy. The movement of electrons in that part of the circuit causes a lot of internal friction and heating.
This heating effect is used in appliances that cook our food and heat our homes. The elements in toasters, hotplates, ovens, kettles, hot water cylinders and bar radiators are all designed to resist the flow of electrons and turn electrical energy into heat energy.
Microwave ovens use a different method to cook our food. A flow of electricity is passed through a device called a magnetron. This produces electromagnetic waves (microwaves) which are absorbed by substances such as food. Tiny particles (mainly water molecules) in the food vibrate rapidly and heat is produced.
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