NTA Abhyas JEE Main2020PhysicsElectromagnetic InductionPractice
A metallic ring (radius R ) of negligible resistance has a resistance r connected across its diameter as shown in the figure. It is moving with velocity v 0 in a constant magnetic field B 0 acting perpendicular to the plane of the paper in the inward direction. The current in the resistance is:
Options
- A2 B R v 0 r
- BB R v 0 r
- CB R v 0 2 r
- D0
Correct answer
A. 2 B R v 0 r
Step-by-step solution
As induced emf is B l v for a moving rod, ∴ the arcs produce of emf of 2 B 0 v 0 R Applying KVL in the loop We get, 2 B 0 v 0 R = i r i = 2 B 0 v 0 R r