Question

calculate the resistance of blok of copper of length 20cm. and cross section area 2cm. the conductivity of copper is 0.59×10^8 ohm/m​

Answer 1

Explanation:

Resistance of copper rod is =

A

ρ

cu

l

=

2×10

−6

1.7×10

−8

×0.2

=0.0017

Resistance of aluminium rod is =

A

ρ

al

l

=

2×10

−6

2.6×10

−8

×0.2

=0.0026

These resistances are in parallel and thus their equvalent resistance is 1mΩ.