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Saturday, 15 August 2026
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Physics Past Questions and Answers

Topic: (a) Electromagnetic Induction

Jamb Physics Questions - (a) Electromagnetic Induction

Question 26:
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 27:
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
Question 28:
The primary coil of a transformer has N turns and is connected to a 120 V a.c. power line. If the secondary coils has 1 000 turns and a terminal voltage of 1 200 volts, what is the value of N?
  • A 120
  • B 100
  • C 1 000
  • D 1 200
View Answer & Explanation
Question 29:
Energy losses through eddy currents are reduced by using
  • A Low resistance wires
  • B Insulated soft iron wires
  • C Few turns of wires
  • D High resistance wires
View Answer & Explanation
Question 30:
In the diagram above , the current I is
  • A <sup style='font-size: smaller;'>3</sup>/<sub style='font-size: smaller;'>8</sub>
  • B <sup style='font-size: smaller;'>9</sup>/<sub style='font-size: smaller;'>11</sub>
  • C <sup style='font-size: smaller;'>11</sup>/<sub style='font-size: smaller;'>9</sub>
  • D <sup style='font-size: smaller;'>8</sup>/<sub style='font-size: smaller;'>3</sub>
View Answer & Explanation