In this post, we have compiled a bunch of interesting numerical problems on Resistivity and Conductivity. These are Solved numerical problems (Worked Solutions).
Resistivity and Conductivity numerical problems (solved worksheet)
1 ) Gold has a conductivity of 45 MS m−1. What is the resistance of a 0.01 m diameter gold connector that is 0.05m long?
First, work out resistivity:
Then, substitute everything possible into the resistivity formula:
4 ) A strand of metal is stretched to twice its original length. What is its new resistance? State your assumptions.
The material does not change, so resistivity is constant. Length doubles and we know that volume must be constant.
V = AL
A = V/L
When we double L, we get:
We are assuming that ρ and V are constant.
3 ) A pure copper wire has a radius of 0.5mm, a resistance of 1 MΩ, and is 4680 km long. What is the resistivity of copper?
4) A material has a conductivity of 106 S m−1. What is its resistivity?