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 751: A metre rule is pivoted at its mid-point with a vertical force of 10N hanging from the distance 30cm from the mid-point. At what distance must a 15N force hang to balance the ruler horizontally? Options:
  A) 30cm
  B) 10cm
  C) 20cm
  D) 25m
  Show Answer
  The correct answer is C .
• Question 752: Which of the following statements is (are) NOT true about the emission of the photoelectrons from metallic surfaces? i. all metallic surfaces emits the same number of photoelectrons in a given light ii. most metallic surfaces emit the same number of photoelectrons in visible and infra-red light iii. a metallic surface emits photoelectrons only if the frequency of the incident light is higher than its own characteristics threshold frequency Options:
  A) i only
  B) ii only
  C) i and ii
  D) ii and iii
  E) iii only
  Show Answer
  The correct answer is E .
• Question 753: Counting of currency notes with moist fingers is based on the principles of? Options:
  A) diffusion
  B) cohesion
  C) adhesion
  D) viscosity
  Show Answer
  The correct answer is C .
• Question 754: A bar magnet is most effectively demagnetized by Options:
  A) placing it in a N - 5 position and hitting it with a hammer
  B) subjecting it to an electric current from a battery
  C) bringing its north pole in contact with the north pole of a very strong magnet
  D) heating the magnet
  Show Answer
  The correct answer is A .
• Question 755: Calculate the heat energy lost when 10g of boiling water changes to ice at 0°C. [Specific latent heat of ice 336Jg^-1 . Specific heat capacity of water 4.2Jg^-1 K^-1] Options:
  A) 840J
  B) 3360J
  C) 3420J
  D) 4200J
  E) 7560J
  Show Answer
  The correct answer is E .
• Question 756: Which of the following conditions are necessary and sufficient for total internal reflection to take place at the boundary between two optical media? i. light is passing from optically denser medium to optically less dense medium. ii. light is passing from optically less dense medium to optically denser medium. iii. angle of incidence is greater. iv. angle of incidence is lesser Options:
  A) i and ii only
  B) ii and iii only
  C) ii and iv only
  D) i and iii only
  E) ii and iv only
  Show Answer
  The correct answer is D .
• Question 757: A man clapping his hands at regular intervals observes that the echo of a clap coincides with the next clap. If the reflecting cliff is 160m away and the speed of sound is 320ms^-1, what is the frequency of the clapping? Options:
  A) 1 Hz
  B) 2Hz
  C) 4Hz
  D) 8Hz
  Show Answer
  The correct answer is A .
• Question 758:

  In semi-conductor, the carriers of current at room temperature are

  Options:
  A) electrons only
  B) electrons and holes
  C) holes only
  D) electron and ions
  Show Answer
  The correct answer is B .
• Question 759: A man stands 4m in front of a plane mirror. If the mirror is moved 1m towards the man, the distance between him and his new image is Options:
  A) 3m
  B) 5m
  C) 6m
  D) 10m
  Show Answer
  The correct answer is C .
• Question 760:

  A sonometer wire is vibrating at frequency f_o. If the tension in the wire is doubted while the length and the mass per unit length are kept constant, the new frequency of vibration is

  Options:
  A) ^f_o/₂
  B) 2f_o
  C) ^f_o/_√2
  D) f_o√2
  Show Answer
  The correct answer is D .