Physics-
General
Easy
Question
A rectangular loop with a sliding connector of length l = 1.0 m is situated in a uniform magnetic field B = 2T perpendicular to the plane of loop. Resistance of connector is r = 2
. Two resistance of 6 and 3 are connected as shown in figure. The external force required to keep the connector moving with a constant velocity v = 2m/s is
- 6 N
- 4 N
- 2 N
- 1 N
The correct answer is: 2 N
Motional emf 
This acts as a cell of emf 
and internal resistance 
.
This simple circuit can be drawn as follows
Current through the connector 
\magnetic force on connector
(Towards left)
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