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General
Easy
Question
A square wire loop of 10.0 cm side lies at right angles to a uniform magnetic field of 20T. A 10 V light bulb is in a series with the loop as shown in the fig. The magnetic field is decreasing steadily to zero over a time interval 
t. The bulb will shine with full brightness if t is equal to
- 20 ms
- 0.02 ms
- 2 ms
- 0.2 ms
The correct answer is: 20 ms
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