Physics Exam Past Questions and Answers | JAMB, WAEC and NECO

Physics is the science that studies the nature and properties of matter and energy. It covers topics like motion, heat, light, sound, electricity, magnetism, and the structure of atoms.

• Question 791: Which of the following is true of sounds? Options:
  A) sound travels faster in air at 20^oC than at 30^oC
  B) the frequency of a given sound wave changes when it crosses the boundary seperating two media
  C) the wavelength of a given sound wave in air decreases as the temperature increases
  D) sound waves cannot be reflected
  Show Answer
  The correct answer is C .
• Question 792:

  

  In the series a.c circuit shown above, the p.d across the inductor is 8V_r.m.s and that across the resistor is 6V_r.m.s. The effective voltage is

  Options:
  A) 2V
  B) 10V
  C) 14V
  D) 48V
  Show Answer
  The correct answer is B .
• Question 793:

  I. A liquid boils when its saturated vapour pressure is equal to the external pressure

  II. Dissolved substances in pure water lead to increase in the boiling point.

  III. When the external pressure is increased, the boiling point increases.

  IV. Dissolved substances in pure water decrease the boiling point.Which combination of the above are peculiarities of the boiling point of a liquid?

  Options:
  A) I, II and III
  B) I, II, III and IV
  C) I, II and IV
  D) II, III and IV
  Show Answer
  The correct answer is A .
• Question 794: The mechanism of heat transfer from one point to another through the vibration of the molecules of the medium is Options:
  A) covection
  B) conduction
  C) radiation
  D) diffusion
  Show Answer
  The correct answer is B .
• Question 795: Which of the following affects the period of a simple pendulum? i. mass of the pendulum bob. ii. length of the pendulum. iii. acceleration due to gravity. Options:
  A) i, ii, and iii
  B) ii and iii only
  C) i and iii only
  D) i and ii only
  Show Answer
  The correct answer is B .
• Question 796: When a negatively charged rod is brought near the cap of a charged gold leaf electroscope which has positive charges, the leaf Options:
  A) Remains the same
  B) Collapses
  C) Collapses and diverges again
  D) Diverges
  Show Answer
  The correct answer is B .
• Question 797: The mass of a specific gravity bottle is 15.2g when it is empty. it is 24.8g when filled with kerosene and 27.2g when filled with distilled water. Calculate the relative density of kerosene Options:
  A) 1.25
  B) 1.10
  C) 0.90
  D) 0.80
  Show Answer
  The correct answer is D .
• Question 798: A machine has a velocity ratio of 5. It requires a 50kg weight to overcome a 200kg weight. The efficiency is Options:
  A) 4%
  B) 5%
  C) 40%
  D) 50%
  E) 80%
  Show Answer
  The correct answer is E .
• Question 799: If a wire 30 cm long is extended to 30.5 cm by a force of 300 N. find the strain energy of wire Options:
  A) 0.75 J
  B) 7.50 J
  C) 75.00 J
  D) 750.00 J
  Show Answer
  The correct answer is A .
• Question 800:

  Which of these is a derived unit?

  Options:
  A) Kilogram
  B) Metre
  C) Newton
  D) Second
  Show Answer
  The correct answer is C .