Physics-
General
Easy
Question
Plane figures made of thin wires of resistance R = 50 milli ohm/metre are located in a uniform magnetic field perpendicular into the plane of the figures and which decrease at the rate dB/dt = 0.1 m T/s. Then currents in the inner and outer boundary are. (The inner radius a = 10 cm and outer radius b = 20 cm)
- 10– 4 A (Clockwise), 2 ' 10– 4 A (Clockwise)
- 10– 4 A (Anticlockwise), 2 ' 10– 4 A (Clockwise)
- 2 ' 10– 4 A (clockwise), 10– 4 A (Anticlockwise)
- 2 ' 10– 4 A (Anticlockwise), 10– 4 A (Anticlockwise)
The correct answer is: 10– 4 A (Clockwise), 2 ´ 10– 4 A (Clockwise)
Current in the inner coil 
length of the inner coil 
so it’s resistance 
According to lenz’s law direction of i1 is clockwise.
Induced current in outer coil 
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