When a generator is being driven at 1200rpm, the generated eml is 130 volts. What is the generated emf, if the speed is reduced to 600rpm, while the field flux remains unchanged?
Correct answer: A. 65V
- A. 65V
- B. 260V
- C. 60V
- D. 10V
Explanation
We know that generated EMF in the DC generator is given by the formula: E = ΦPNZ/60A Where Φ= flux P= No. of poles N= speed Z= No. of conductors A= No. of paths Hence E ∝ ΦN E2/E1 = Φ2/Φ1 X N2/N1 ~since field flux remains unchanged hence it will be cancelled and so: E2/E1 = N2/N1 E2/130 = 600/1200 E2= 65 V (hence it is the generated emf)
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About Faraday's Law
Faraday's law states that an induced electromotive force equals the rate of change of magnetic flux linkage through a circuit. Questions cover changing field, area, angle or motion, the negative sign associated with Lenz's law, and the distinction between induced emf and the current that may flow in a closed circuit.
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