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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 16:
Which of the following ammeters may be used to measure alternating currents? i. moving-coil ammeter ii. moving-iron ammeter iii. hot-wire ammeter
  • A I and ii only
  • B Ii and iii only
  • C I and iii only
  • D I, ii, and iii
View Answer & Explanation
Question 17:
The principle of operation of an induction coil is based on
  • A Ohm's law
  • B Amphere's law
  • C Faraday's law
  • D Columbs law
View Answer & Explanation
Question 18:
To convert an alternating current dynamo into a direct current dynamo, the
  • A Number of turns in the coil is increased
  • B Strength of the field magnet is increased
  • C Slip rings are replaced with a split ring commutator
  • D Coil is wound on a soft iron armature
View Answer & Explanation
Question 19:
The current I in the fig above is
  • A 4.00A
  • B 1.30A
  • C 0.80A
  • D 0.75A
View Answer & Explanation
Question 20:
The primary winding of a transformer has 400 turns and its secondary has 100 turns. If a source of e.m.f. of 12V is applied to the primary, the secondary e.m.f. will be
  • A 3V
  • B 6V
  • C 24V
  • D 48V
View Answer & Explanation