Question

The electrical resistivity of three materials A, B and C at 20°C is given below:

Material	Resistivity (Ω m)
A	1017
B	44 × 10−6
C	1.62 × 10−8

1. Classify these materials as conductor, alloy and insulator.
2. Give one example of each of these materials and state one use of each material in the design of an electrical appliance say an electric stove or an electric iron.

Answer 1

i. 

Conductor	Insulator	Alloy
C	A	B

ii. 

Material	Example	Use
A	Ceramic	Used in bulb holders
B	Nichrome	Making toasters
C	Copper	Making power cords