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 131: A light of energy 5eV falls on a metal and the electrons with a maximum kinetic energy of 2eV are ejected. The work function of the metal is Options:
  A) 0.4eV
  B) 2.5eV
  C) 3.0eV
  D) 7.0eV
  Show Answer
  The correct answer is C .
• Question 132: Primary colours of light are Options:
  A) Red, blue and green
  B) Cyan, magneta and yellow
  C) Black, blue and green
  D) None of these colours
  Show Answer
  The correct answer is A .
• Question 133:

  A car of mass 800kg attains a speed of 25m/s in 20secs. The power developed in the engine is

  Options:
  A) 1.25 x 10${}^4$W
  B) 2.50x 10${}^4$W
  C) 1.25 x 10${}^6$W
  D) 2.50 x 10${}^6$W
  Show Answer
  The correct answer is A .
• Question 134: 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 135:

  A piano wire 50 cm long has a total mass of 10 g and its stretched with a tension of 800 N. Find the frequency of the wire when it sounds its third overtone note.

  Options:
  A) 800 Hz
  B) 600 Hz
  C) 400 Hz
  D) 200 Hz
  Show Answer
  The correct answer is A .
• Question 136: Which of the following statements describes an atom accurately? i. atoms of all elements are identical ii. an atom contains a nucleus and number of electrons iii. due to the electrons in the atom an atom is negatively charged iv. electrons in the atom move in circular orbits round the nucleus Options:
  A) i and ii
  B) ii and iii
  C) iii and iv
  D) ii and iv only
  E) i,ii and iii
  Show Answer
  The correct answer is D .
• Question 137:

  Which of the following is not correct about the molecules of a substance in a gaseous state. They?

  Options:
  A) are in a constant state of motion
  B) have different speeds
  C) have a temperature which is measured by the average kinetic energy
  D) The collision between the gases is perfectly inelastic
  Show Answer
  The correct answer is D .
• Question 138: A cell has an open circuit voltage V₁ and a closed circuit voltage V₂ when a current is flowing through it. Therefore, the internal resistance of the cell is Options:
  A) $\frac{V_2}{I}$
  B) $\frac{V_1}{I}$
  C) $\frac{(V_1+V_2)}{I}$
  D) $\frac{(V_1-V_2)}{I}$
  E) $\frac{(V_2-V_1)}{I}$
  Show Answer
  The correct answer is E .
• Question 139: Radio waves emitted from an antenna are picked up by a radar after reflection from an aircraft in 4 x 10^-3S. How far is the aircraft from the antenna? [c = 3 x 10⁸ms^-1 ] Options:
  A) 6.0 x 10²ms^-1
  B) 1.2 x 10³km
  C) 3.0 x 10³km
  D) 6.0 x 10 ⁵km
  Show Answer
  The correct answer is D .
• Question 140: In a semi conductor junction diode, as the depletion or barrier layer is forward-biased, the layer Options:
  A) widens
  B) narrows
  C) remains constant
  D) widens then narrows
  Show Answer
  The correct answer is C .