The magnitude of the earth's magnetic field at the north pole is `B_(0)` . A horizontal conductor of length `l` moves with a velocity `v` . The direction of `v` is perpendicular to the conductor. The induced emf is
(i) zero, if `v` is vertical
(ii) `B_(0)lv` , if `v` is vertical
(iii) zero, if `v` is horizontal
(iv) `B_(0)lv` , if `v` is horizontal

Options

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

Answer

C

Explanation

At north pole, `vec(B)=-B_(0)hatk`
(i) `vec(v)=vhatK` , `e=0`
(ii) `vec(v)=vhati` , `l=lhatj` , `e=B_(0)vl`