Physics-
General
Easy
Question
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 the ring is V and the potential difference developed across the ring is
- Zero
and M is at higher potential
and Q is at higher potential
- 2RBV and Q is at higher potential
and M is at higher potential
and Q is at higher potential
The correct answer is: 2RBV and Q is at higher potential
Rate of decrease of area of the semicircular ring 
According to Faraday's law of induction induced emf
The induced current in the ring must generate magnetic field in the upward direction. Thus Q is at higher potential.
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