The tightly wound coils are nichrome wires these are the wires having an immense resistivity and a vwery high melting point and are much more durable ,they offer a great resistance to the current and so the energy loses its identity of electrical energy to heat energy to give out intense infrared radiations .
That is why they are used to provide heat . Nichrome is an alloy of two elements ,as the name suggests (ni - chrome) it is an alloy of Nickel and Chromium.
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