A conducting disc of radius `R` is rolling without sliding on a horizontal surface with a constant velocity `v`.A uniform magnetic field of strength `B` is applied normal to the plane of the disc.Find the `EMF` induced between (at this moment )
(a)`P&Q` , (b)`P&C` , (c )`Q&C`
(`C` is centre `P&Q` are opposite points on vertical diameter of the disc)