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Sunday, 21 June 2026
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Physics Past Questions and Answers

Topic: Electromagnetic Induction

Jamb Physics Questions - Electromagnetic Induction

Question 31:
A transformer is rated 240v. If the primary coil is 4000 turns and the secondary voltage 12v, determine the number of turns in the secondary coil.
  • A 200
  • B 100
  • C 250
  • D 150
View Answer & Explanation
Question 32:
Lenz's law is a law of conservation of
  • A Electric charge
  • B Electric current
  • C Energy
  • D Momentum
View Answer & Explanation
Question 33:
A band of 500 rectangular loops of wire of area 20 cm by 20 cm, encloses a region of magnetic field which charges from 1.0T to 0.4T within 5 seconds, calculate the induced e.m.f.
  • A 5.60 v
  • B 24.00 v
  • C 0.24 v
  • D 2.40 v
View Answer & Explanation
Question 34:
A semiconductor diode is used in rectifying alternating current into direct current mainly because it
  • A Allows current to flow in either direction
  • B Is non-linear
  • C Offers a high input resistance
  • D Allows current to flow only in one direction
View Answer & Explanation
Question 35:
A conductor of length 2m carries a current of 0.8A while kept in a magnetic field of magnetic flux density 0.5T. The maximum force acting on it is
  • A 0.2N
  • B 0.8N
  • C 3.2N
  • D 8.0N
View Answer & Explanation