Physics-
General
Easy
Question
A pair of parallel conducting rails lie at right angle to a uniform magnetic field of 2.0 T as shown in the fig. Two resistors 10 W and 5 
are to slide without friction along the rail. The distance between the conducting rails is 0.1 m. Then
- Induced current
directed clockwise if 10 resistor is pulled to the right with speed 0.5 ms–1 and 
resistor is held fixed
- Induced current
directed anti-clockwise if 10 resistor is pulled to the right with speed 0.5 ms–1 and resistor is held fixed
- Induced current directed clockwise if 5 resistor is pulled to the left at 0.5 ms–1 and 10 resistor is held at rest
- Induced current directed anti-clockwise if 5 resistor is pulled to the left at 0.5 ms–1 and 10 resistor is held at rest
directed clockwise if 10 resistor is pulled to the right with speed 0.5 ms–1 and resistor is held fixed
directed anti-clockwise if 10 resistor is pulled to the right with speed 0.5 ms–1 and resistor is held fixed
directed clockwise if 5 resistor is pulled to the left at 0.5 ms–1 and 10 resistor is held at rest
directed anti-clockwise if 5 resistor is pulled to the left at 0.5 ms–1 and 10 resistor is held at rest
The correct answer is: Induced current directed anti-clockwise if 5 resistor is pulled to the left at 0.5 ms–1 and 10 resistor is held at rest
When resistor is pulled left at 0.5 m/sec induced emf., in the said resistor = 
Resistor 
is at rest so induced emf in it 
be zero.
Now net emf.,
in the circuit 
and equivalent
resistance of the circuit
R = 15 W
Hence current 
And its direction will be anti-clockwise (according to Lenz’s law)
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