Question

Consider an infinitesimal portion dQ of the rod a distance x from the origin. Write an expression for the magnitude dE of the electric field at point P, created by this portion.

Answer 1

The electric field dE due to charge dQ is given as:

dE = (KdQ/r) * r^.

r^ is vector position

r^ = sqrt(x2 + a2). Pythagoras theorem.

K is electrostatic constant. K = 1/4πe(0)