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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 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:
What precaution should a manufacturer take to ensure that energy loss in a transformer is minimized?
  • A The winding of the transformer should be made of high resistance wire
  • B The core should be made of thin sheets of metal
  • C No magnetic material should be used to make the core
  • D The flux linking the primary with the secondary coils should be minimum
View Answer & Explanation
Question 19:
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 20:
If a current carrying coil is mounted on a metal frame, the back e.m.f. induced in the coil causes
  • A Inductance
  • B Eddy currents
  • C Elecro-magnetism
  • D Dipole moment
View Answer & Explanation