Question

the length of a straight the wire is 2m. it is uniformly charged with a positive charge of 3mu C. calculate the charge density of the wire.​

Answer 1

We don't really need to write an integral, we just need the charge per unit length in the cylinder to be equal to zero. This means that the positive charge in cylinder must be +3.60nCm

−1

. This positive charge is uniformly distributed in a circle of radius R=1.50cm, so

ρ=

π(0.015m)

2

3.60nCm

−1

=5μCm

−3