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Sunday, 21 June 2026
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Physics Past Questions and Answers

Topic: Current Electricity

Jamb Physics Questions - Current Electricity

Question 46:
Electricity is supplied to a school along a cable of total resistance 0.5\(\Omega\) with the maximum current drawn from the mains as 100A. The maximum energy dissipated as heat for 1 hr is
  • A 3.6 x 10<sup style='font-size: smaller;'>3</sup>J
  • B 5.0 x 10<sup style='font-size: smaller;'>3</sup>J
  • C 3.0 x 10<sup style='font-size: smaller;'>5</sup>J
  • D 1.8 x 10<sup style='font-size: smaller;'>7</sup>J
View Answer & Explanation
Question 47:
A 3000W electric cooker is to be used on a 200V mains circuit. Which of the fuses below can be used safely with the cooker?
  • A 2A
  • B 5A
  • C 10A
  • D 20A
View Answer & Explanation
Question 48:
A galvanometer has a resistance of 5Ω. By using a shunt wire of resistance 0.05Ω, the galvanometer could be converted to an ammeter capable of reading 2Amp. What is the current through the galvanometer?
  • A 2mA
  • B 10mA
  • C 20mA
  • D 25mA
View Answer & Explanation
Question 49:
In the circuit above, the ammeter reads a current of 5.0 A when R = 8Ω and reads 7.0A when R = 5Ω. The value of the unknown resistance X is
  • A 10.0Ω
  • B 7.5Ω
  • C 5.0Ω
  • D 2.5Ω
View Answer & Explanation
Question 50:
An electron of charge 1.6 x 10-19C and mass 9.1 x 10-31kg is accelerated between two metal plates with a velocity of 4 x 107ms-1, the potential difference between the plates is
  • A 4.55 x 10<sup style='font-size: smaller;'>3</sup>V
  • B 4.55 x 10<sup style='font-size: smaller;'>2</sup>V
  • C 9.10 x 10<sup style='font-size: smaller;'>1</sup>V
  • D 4.55 x 10<sup style='font-size: smaller;'>1</sup>V
View Answer & Explanation