question_answer

  Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?                                                                [NCERT]

Answer:

                  (i) Among iron and mercury, iron is better conductor of electricity because resistivity of iron (10.0 x 10-8 m) is less than that of mercury (94.0 X 10-8m). (ii) We know that a good conductor of electricity should have a low resistivity. Silver has the lowest resistivity of 1.60 x 10-8 m, which means that silver offers the least resistance to the flow of current through it. So, silver is the best conductor of electricity.