Question

Two large metal sheets carry surface currents as shown in figure (35-E13). The current through a strip of width dl is Kdl where K is a constant. Find the magnetic field at the points P, Q and R.

Answer 1

(a) At point P, i = 0, Thus B = 0

(b) At point R, i = 0, B = 0

(c) At point θ,

Applying ampere’s rule to the above rectangle

Since the vector B due to the 2 stripes are along the same direction, thus.