Search SchoolNGR

Wednesday, 28 October 2026
Register . Login

Physics Past Questions and Answers

Jamb 1978 Physics Questions

Question 26:
In a D.C. circuit, a 10 microfarad (mf) capacitor is placed in series with a 10 0hm resistor. The total resistance of the combination is
  • A 10 ohms
  • B 1 ohms
  • C Zero
  • D 20 ohms
  • E Infinite
View Answer & Explanation
Question 27:
On an a.c generator, which of the following does not apply?
  • A Field magnet
  • B Commutator
  • C Armature
  • D Slip rings
  • E Carbon brushes
View Answer & Explanation
Question 28:
Why is it impossible for the lines of force of an electric field to cross one another?
  • A Like charges repel each other
  • B A charged particle is deflected by an eletric field
  • C Like charges are arranged on the same line of force
  • D A positively charged particle can travel in only one direction at any time
  • E None of these is correct
View Answer & Explanation
Question 29:
A potential difference of 6v is used to produce a current of 5A for 200s through a heating coil. The heat produced is
  • A 4800 cal
  • B 6000 cal
  • C 2400J
  • D 240k cal
  • E 6000J
View Answer & Explanation
Question 30:
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