MHT CET Medical202623 April 2026Evening ShiftPhysicsElectromagnetic InductionActual
A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic induction B. At the position MNQ the speed of ring is V and emf developed across the ring is
Options
- Azero
- B2 RBV and Q is at higher potential
- CRBV and Q is at higher potential
- DBV R^2 2 and M is at higher potential
Correct answer
B. 2 RBV and Q is at higher potential
Step-by-step solution
The induced motional emf in an arbitrarily shaped moving conductor in a uniform magnetic field is equivalent to the emf induced in a straight conductor connecting its two ends. The effective length of the semicircular ring is the straight line distance between its ends M and Q. Effective length l = 2R The magnitude of the motional emf developed is given by = Bvl Substituting the values, we get = B V 2R = 2RBV To determine the polarity, we consider the magnetic force on a positive charge carrier, given by F = q( V B