Question

A straight line of charge of length 12 cm carries a uniformly distributed charge of 0.3 × 10^-6 coulombs per cm length. Determine the magnitude and direction of the electric field intensity at a point 

(i) Located at a distance of a 3 cm above the wire displaced 3 cm to the right of and beyond one end. 

(ii) Located at the distance of 3 cm from one end, in alignment with, but beyond the wire. 

(iii) Located at a distance of 3 cm from one end, on the wire itself.

Answer 1

(ii) consider an element dx of charge λdx at a distance x from A. The field at P due to the positive charge element λdx is directed to the right.

(iii) Now L = AC = 6 cm = 0.06 cm 

h = 0.03 m