Search SchoolNGR

Monday, 17 August 2026
Register . Login

Physics Past Questions and Answers

Topic: Concepts of electrical energy and power

Jamb Physics Questions - Concepts of electrical energy and power

Question 1:
The electric supply from Kainji Dam is transmitted at high voltages of the order hundreds of kilovolts but is converted to domestic use of about 220 volts by
  • A Commutators
  • B Transistors
  • C Valves and diodes
  • D Rectifiers
  • E Transformers
View Answer & Explanation
Question 2:
Which of the following statements on the use of X-rays is incorrect? X-rays are used
  • A In hospitals to obtain photogaphs of tissues and bones in the body
  • B For the treatment of malignant growths like cancer cells
  • C In detecting fingerprints
  • D To reveal hidden flaws in metal castings and welded joints
  • E To detect alternations which have been made to works of art
View Answer & Explanation
Question 3:
The resistance of a 240V, 60 watt electric filament bulb is
  • A 0.25\(\Omega\)
  • B 480\(\Omega\)
  • C 60\(\Omega\)
  • D 240\(\Omega\)
  • E 960\(\Omega\)
View Answer & Explanation
Question 4:
What is the cost of running five 50W lamps and four 100W lamps for 10 hours if electrical energy costs 2 kobo per kWh?
  • A N0.65
  • B N0.13
  • C N3.90
  • D N39.00
  • E N234.00
View Answer & Explanation
Question 5:
The cost of running five 60 W lamps and four 100 W lamps for 20 hours if electrical energy cost #10.00 per kwh is
  • A 280.00
  • B 160.00
  • C 120.00
  • D 140.00
View Answer & Explanation