Question

A conductor ABCDE, shaped as shown, carries current I. It is placed in the x-y plane with the end A and E on the x-axis. A uniform magnetic field of magnitude B exists in the region. The force acting on it will be

A. (i), (ii)
B. (ii), (iii)
C. (iii), (iv)
D. (i), (ii), (iii)

Answer 1

Correct Answer - D
If wire other than straight wire, join initial and final ends of wire and the straight wire is effective wire

(i) if `vec(B) = Bhat(i), vec(F)_(m) = i(lambda hat(i) xx B hat(i)) = 0`
(ii) `vec(B) = Bhat(j), vec(F)_(m) = i(lambda hat(i) xx B hat(j)) = Bi lambda hat(k)`
(iii) `vec(B) = Bhat(k), vec(F)_(m) = i(lambda hat(i) xx B hat(k)) = Bi lambda hat(j)`