Question:
A copper disc of diameter $20\, cm$ makes $1200\, r.p.m$. about its natural axis kept parallel to a uniform magnetic field of $10^{-2}$ T. The potential difference between the centre and edge of the disc is
A copper disc of diameter $20\, cm$ makes $1200\, r.p.m$. about its natural axis kept parallel to a uniform magnetic field of $10^{-2}$ T. The potential difference between the centre and edge of the disc is
Updated On: Jul 5, 2022
- $6.28 \times 10^{-3}\,V$
- $62.8 \times 10^{-3}\,V$
- $0.628 \times 10^{-3}\,V$
- 0.628 V
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The Correct Option is B
Solution and Explanation
$e = \frac{1}{2} BR^\, omega$ where $\omega = 2 \pi \, f$
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Concepts Used:
Electromagnetic Induction
Electromagnetic Induction is a current produced by the voltage production due to a changing magnetic field. This happens in one of the two conditions:-
- When we place the conductor in a changing magnetic field.
- When the conductor constantly moves in a stationary field.
Formula:
The electromagnetic induction is mathematically represented as:-
e=N × d∅.dt
Where
- e = induced voltage
- N = number of turns in the coil
- Φ = Magnetic flux (This is the amount of magnetic field present on the surface)
- t = time
Applications of Electromagnetic Induction
- Electromagnetic induction in AC generator
- Electrical Transformers
- Magnetic Flow Meter