Q33 of 330 Page 20

A p.d. of 10 V is needed to make a current of 0.02 A flow through a wire. What p.d. is needed to make a current of 250 mA flow through the same wire?

Here I₁ = 0.02 amp, V₁ = 10 volt

V=IR

Again

Here I₂ = 250mA=0.25A, R = 500

V₂=I₂R =0.25×500=125V

Name the electrical property of a material whose symbol is “omega”.

The graph between V and I for a conductor is a straight line passing through the origin.

(a) Which law is illustrated by such a graph?

(b) What should remain constant in a statement of this law?

A current of 200 mA flows through a 4 KΩ resistor. What is the p.d. across the resistor?

What happens to the resistance as the conductor is made thicker?