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 811: Which of the following representations is correct for an atom X with 28 electrons and 30 neutrons? Options:
  A) ${}_{28}^{58}X$
  B) ${}_{28}^{30}X$
  C) ${}_{30}^{28}X$
  D) ${}_{30}^{58}X$
  Show Answer
  The correct answer is A .
• Question 812:

  I. The earth is not spherical but elliptical in shape
  II. Variation in latitude and longitude
  III. Rotation of the earth on its axis
  IV. Variation in the density of the earth

  On which combination of the above does the weight of an object vary on the earth's surface?

  Options:
  A) I, II, III and IV
  B) II, III and IV only
  C) I, II and III only
  D) I and II only
  Show Answer
  The correct answer is D .
• Question 813: The half-life of a radio-active element is 9 days, what fraction of atoms has decayed in 36 days? Options:
  A) $\frac{1}{16}$
  B) $\frac{1}{4}$
  C) $\frac{1}{2}$
  D) $\frac{15}{16}$
  Show Answer
  The correct answer is D .
• Question 814: The current in a reverse-biased junction is due to? Options:
  A) minority carriers
  B) electrons
  C) majority carriers
  D) holes
  Show Answer
  The correct answer is A .
• Question 815:

  Which of these is observed when air is pumped out of a discharge tube without lowering its pressure

  Options:
  A) the conductivity of the air increases
  B) the conductivity of the air decreases
  C) conduction does not occur
  D) spark are produced
  Show Answer
  The correct answer is C .
• Question 816: 10⁶J of heat is required to boil off completely 2kg of a certain liquid. Neglecting heat lost to the surroundings, the latent heat of vaporization of the liquid is Options:
  A) 2.0 x 10⁶J kg^-1
  B) 5.0 x 10⁶J kg^-1
  C) 2.0 x 10⁵J kg^-1
  D) 5.0 x 10⁵J kg^-1
  Show Answer
  The correct answer is D .
• Question 817:

  An open-tube mercury manometer is used to measure the pressure in a gas tank. When the atmospheric pressure is 101,325 $P_a$, what is the absolute pressure in $P_a$ in the tank if the height of the mercury in the open tube is 25 cm higher. density of mercury = $13600kg/m^3,g=9.8m/s^2$

  Options:
  A) 108,986 Pa
  B) 165,238 Pa
  C) 122,364 Pa
  D) 134,645 Pa
  Show Answer
  The correct answer is D .
• Question 818:

  A machine gun with a mass of 5kg fires a 50g bullet at a speed of 100 ms${}^{-1}$. The recoil speed of the machine gun is

  Options:
  A) 0.5 ms${}^{-1}$
  B) 1.5 ms${}^{-1}$
  C) 1 ms${}^{-1}$
  D) 2ms${}^{-}1$
  Show Answer
  The correct answer is C .
• Question 819: What is the angular magnification of a telescope having objective and eyepiece lenses of a focal lengths 30cm and 3cm respectively? Options:
  A) 60
  B) 10
  C) 30
  D) 90
  Show Answer
  The correct answer is B .
• Question 820: If the relative density of gold is 19.2, the volume of 2.4kg of gold is? Options:
  A) 8.00 x 10^-3 m³
  B) 1.25 x 10^-4 m³
  C) 1.92 x 10^-4 m³
  D) 4.61 x 10^-3 m³
  Show Answer
  The correct answer is B .