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 711:

  An a.c of 1A at a frequency of 800 cycles per second flows through a coil, the inductance of which is 2.5mH and the resistance of which is 5Ω. What is the power absorbed in the Coil?

  Options:
  A) 5W
  B) 6W
  C) 7W
  D) 8W
  Show Answer
  The correct answer is A .
• Question 712: The energy associated with the emitted photon when a mercury atom changes from one state to another is 3.3 ev. calculate the frequency of the photon.
  [e = 1.6 x 10^-19c; h = 6.6 x 10^-13js] Options:
  A) 1.3 x 10^-15 Hz
  B) 3.1 x 10⁵² Hz
  C) 3.2 x 10^-53 Hz
  D) 8.0 x 10¹⁴ Hz
  Show Answer
  The correct answer is D .
• Question 713:

  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 .
• Question 714:

  During the transformation of matter from the solid to the liquid state, the heat supplied does not produce temperature increase because

  Options:
  A) all the heat is used to break the bonds holding the molecules of the solid together
  B) the heat capacity has become very large as the substance melts
  C) the heat energy is quickly conducted away
  D) the heat gained is equal to the heat lost by the substance
  Show Answer
  The correct answer is A .
• Question 715: An a.c circuit of e.m.f 12V has a resistor of resistance 8Ω connected in series to an inductor of inductive reactance 16Ω and a capacitor capacitive reactance 10Ω. The current flow in the circuit is Options:
  A) 1.4A
  B) 1.2A
  C) 12.0A
  D) 14.0A
  Show Answer
  The correct answer is B .
• Question 716: Which of the following phenomena explains the formation of a mirage? i. Reflection ii. Refraction iii. Diffraction Options:
  A) i and ii only
  B) ii and iii only
  C) i and iii only
  D) i, ii, and iii only
  Show Answer
  The correct answer is A .
• Question 717: in a pure semiconductor, the number of electrons in the conduction band is Options:
  A) less than the number of holes in the valence band
  B) equal to the number of holes in the valence band
  C) greater than the number of holes in the valence band
  D) twice the number of holes in the valence band
  Show Answer
  The correct answer is B .
• Question 718:

  A boy standing some distance from the foot of a tall cliff claps his hands and hears an echo 0.5s later. If the speed of sound is 340ms${}^{-1}$, how far is he from the cliff?

  Options:
  A) 680m
  B) 170m
  C) 34m
  D) 85m
  Show Answer
  The correct answer is D .
• Question 719:

  The pitch of a screw jack is 0.45cm and the arm is 60cm long. If the efficiency of the Jack is 75/π %, calculate the mechanical advantage.

  Options:
  A) 400
  B) 300
  C) 200
  D) 150
  Show Answer
  The correct answer is C .
• Question 720:

  Heat is supplied uniformly at the rate of 100W to 1.0 x 10${}^{-2}$kg of a liquid for 20 seconds. If the temperature of the liquid rises by 5${}^o$C, then the specific heat capacity of the liquid is

  Options:
  A) 2.0 x 10${}^2$Jkg${}^{-}1$K${}^{-}1$
  B) 2.0 x 10${}^2$Jkg${}^{-}1$
  C) 4.0 x 10${}^4$Jkg${}^{-}1$K${}^{-}1$
  D) 4.0 x 10${}^4$Jkg${}^{-}1$
  Show Answer
  The correct answer is C .