Discuss the desirable characteristics of the heating coil used in electric iron and heater.
The desirable characteristic features of the heating coil used in electric iron and heater should be: (i)It should have a high resistivity so that appreciable amount of heat is produced due to passage of current through a high resistance. (ii)The material should have high melting which will prevent it from melting. (iii)It should not get oxidised easily up to temperature of 10000c. (iv)The material should have low-value thermal coefficient of linear expansion otherwise it may loosen on getting heated thereby can cause insulation rupture-related problems.