question_answer 53)

  A uniform conducting wire of length 12 a and resistance R is wound up as a current carrying coil in the shape of (i) an equilateral triangle of side a; (ii) a square of sides a and, (iii) a regular hexagon of sides a. The coil is connected to a voltage source . Find the magnetic moment of the coils in each case.

Answer:

                  (i) Refer Fig. 3(EP).8(a); No. of turns, n = 4                  Area of triangle (ii) Refer Fig. 3(EP).8(b) ; n = 3, area A = a x a = (iii) Refer Fig. 3(EP).8(c) ; n = 2, area Magnetic moment, M = For (i)                 For (ii) For (iii),