Question

material ?
15. () Write down an expression for the resistance of a metallic wire in terms of the resistivity,
What will be the resistance of a metal wire of length 2 metres and area of cross-section
1.55 x 10+ m², if the resistivity of the metal be 2.8 x 10-8 m ?
16. (a) Give two examples of substances which are good conductors of electricity. Why do you think they are​

Answer 1

The resistance of an electric circuit is defined as the ratio of the voltage applied on it to the electric current that passes through it.

The resistivity of a wire depends on the material that is used to make the wire.

The resistance of a metallic wire in terms of resistivity is given as

R = ρl/A

where

R = resistance of the wire

ρ = resistance of the wire

l = length of the wire

A = cross-sectional area of the wire