The electrical resistivities of five substances A, B, C, S, and E are given below: A = 5.20×10-8 Ωm B = 110×10-8 Ωm C = 2.60×10-8 Ωm D = 10.0×10-8 Ωm E = 1.70×10-8 Ωm a) Which substance is the best conductor of electricity? Why? b) Which one is a better conductor: A or C? Why? c) Which substance would you advice to be used for making heating elements of electric irons? Why? Which two substances should be used for making electric wires? Why?
ScienceClass 10ICSEAnswered 27 Mar 2026
Answer
- E is the best conductor of electricity because it has the least resistivity
- C is a better conductor between A and C because the resistivity of C is lesser than that of A
- B can be used in the making of the heating elements of an electric iron because the resistivity of B is the highest
- C and E are the two substances that should be used for making electric wires because they have low electrical resistivities