In a coil of resistance \(100~\Omega\), a current is induced by changing the magnetic flux through it (as shown in the graph). The magnitude of the change in flux through the coil is:

                   
1. \(200~\text{Wb}\)
2. \(225~\text{Wb}\)
3. \(250~\text{Wb}\)
4. \(275~\text{Wb}\)

Subtopic:  Magnetic Flux |
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A circular ring is placed in a magnetic field of \(0.4\) T. Suddenly its radius starts shrinking at the rate of \(1\) mm/s. What will be the induced EMF in the ring at \(r = 2~\text{cm?}\) 
1. \(16 \pi~\mu \text{V}\)
2. \(8 \pi~\mu \text{V}\)
3. \(16 \pi~ \text{mV}\)
4. \(8 \pi~ \text{mV}\)
Subtopic:  Magnetic Flux |
 66%
From NCERT
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