A vertical conduction ring of radius `R` falls vertically in a horizontal magnetic field of magnitude `B` with constant speed `v` . The direction of `B` is perpendicular to the plane of the ring. When the speed of the ring is `v` , (i) `A` and `D` are at different potential
(ii) `A` and `D` are at the same potential
(iii) `C` and `E` are at the same potential
(iv) The potential difference between `A` and `D` is `2BRv` , with `D` a higher potential

Options

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

Answer

C

Explanation

`V_(D)-V_(A)=e=B.v.2R=2BvR`
`V_(C)-V_(E)=0` .