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WAEC Physics: practice questions.
12 free questions with answers and explanations, plus the topics to revise.
Below are free WAEC Physics practice questions with answers and explanations. They are original eZine questions, written and reviewed by teachers in the style of the WAEC WASSCE; we do not publish past questions. eZine's published WAEC Physics bank holds 505 questions across 73 topics (counted 29 October 2026); the largest topics are Motion, Light waves I, Electric Field.
eZine's WAEC subject mock uses 50 questions in 60 minutes estimated. WAEC sets the objective paper's length per subject and publishes it in each subject's syllabus; eZine holds no WAEC paper figures yet, so this is a practice default.
WAEC Physics practice questions
Choose an option to check it, or open the answer. Each is an eZine practice question (original, teacher-reviewed).
Question 1 · Heat Energy: Temperature and its measurement I
The thermometric property used in a constant-volume gas thermometer is the
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Answer: B. pressure of a fixed mass of gas at constant volume
As the name says, the volume is kept constant and the pressure of the gas, which changes with temperature, is measured. Volume at constant pressure is the constant-pressure gas thermometer. Length of liquid is the liquid-in-glass thermometer. Resistance is the resistance thermometer.
eZine practice question (original, teacher-reviewed)
Question 2 · Electric Field
An electric bulb is rated 60 W, 240 V. What is its resistance when working normally?
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Answer: D. 960 Ω
P = V^2/R, so R = V^2/P = 240^2/60 = 57 600/60 = 960 Ω. 4 Ω is V/P; 14 400 Ω multiplies P by V; 0.25 Ω is P/V (which is actually the current in amperes, 0.25 A).
eZine practice question (original, teacher-reviewed)
Question 3 · Heat Energy Measurements I
Beans cook faster in a pressure pot than in an open pot because
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Answer: D. the increased pressure raises the boiling point of the water
Boiling point rises with external pressure, so the water inside boils at above 100 °C (about 120 °C), cooking faster. Lower boiling point would slow cooking (as happens on high mountains). The amount of water is not the reason. The steam is hotter, not cooler.
eZine practice question (original, teacher-reviewed)
Question 4 · Quantities and Measurements
On a vernier caliper whose least count is 0.01 cm, the zero of the vernier scale lies just past the 2.3 cm mark on the main scale, and the 6th vernier division coincides with a main-scale division. What is the reading?
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Answer: C. 2.36 cm
Reading = main-scale reading + (coinciding vernier division x least count) = 2.3 + 6 x 0.01 = 2.36 cm. 2.90 cm treats each vernier division as 0.1 cm; 2.306 cm uses 0.001 cm; 2.24 cm subtracts instead of adding.
eZine practice question (original, teacher-reviewed)
Question 5 · Physics and Biogas Production
Biogas produced from cow dung in a digester is mainly
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Answer: B. methane
Biogas is about 50–70 % methane, with carbon dioxide and traces of hydrogen sulphide, produced by anaerobic digestion. Oxygen is not produced (the process is anaerobic). Hydrogen sulphide is only a trace impurity. Nitrogen is not the main component.
eZine practice question (original, teacher-reviewed)
Question 6 · Heat Energy
A steel rod is 2.0 m long at 20 °C. Its linear expansivity is 1.2 x 10^-5 K^-1. By how much does it lengthen when heated to 70 °C?
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Answer: C. 1.2 mm
delta L = alpha L delta theta = 1.2 x 10^-5 x 2.0 x 50 = 1.2 x 10^-3 m = 1.2 mm. 0.6 mm leaves out the original length of 2.0 m; 12 mm is a unit-conversion slip; 0.024 mm leaves out the temperature change.
eZine practice question (original, teacher-reviewed)
Question 7 · Software and Data Analysis
In Microsoft Excel, a student has typed ten period readings in cells B2 to B11. Which formula gives their mean?
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Answer: C. =AVERAGE(B2:B11)
AVERAGE with a colon range B2:B11 averages all ten cells. MEAN is not an Excel function, so it returns an error. AVERAGE(B2,B11) with a comma averages only the two cells B2 and B11. SUM/2 divides by 2 instead of 10.
eZine practice question (original, teacher-reviewed)
Question 8 · Application of lenses and mirrors as optical instruments
The image formed on the sensor (or film) of a camera is
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Answer: A. real, inverted and diminished
A camera's converging lens forms a real image (it falls on the sensor) of distant objects beyond 2F: inverted and smaller than the object. A virtual image could not be recorded on the sensor. Upright same-size images are not formed by a single converging lens on a screen.
eZine practice question (original, teacher-reviewed)
Question 9 · Quantities and Measurements
Which instrument is most suitable for measuring the diameter of a thin copper wire (about 0.5 mm)?
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Answer: A. Micrometer screw gauge
A micrometer reads to 0.01 mm, giving three significant figures for 0.5 mm. A metre rule and a tape rule read only to 1 mm, larger than the wire itself. Vernier callipers read to 0.1 mm (0.01 cm), too coarse for a 0.5 mm wire.
eZine practice question (original, teacher-reviewed)
Question 10 · Concept and properties of light II
Total internal reflection occurs only when light
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Answer: A. passes from a denser to a less dense medium with i greater than the critical angle
Both conditions are needed: denser to less dense medium (e.g. glass to air) and i > C. Going into a denser medium the ray bends towards the normal and is never totally reflected. A silvered surface gives ordinary reflection. Along the normal the angle of incidence is 0°, less than C.
eZine practice question (original, teacher-reviewed)
Question 11 · Elasticity
A spring obeys Hooke's law and extends by 4 cm when a force of 20 N is applied. What is its force constant?
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Answer: A. 500 N/m
k = F/e = 20 N / 0.04 m = 500 N/m. 5 N/m divides by 4 without converting cm to m; 80 N/m multiplies F by e; 0.002 N/m inverts the ratio.
eZine practice question (original, teacher-reviewed)
Question 12 · Equilibrium of Forces II
A stone weighs 5.0 N in air and 3.2 N when fully immersed in water. What is the relative density of the stone?
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Answer: C. 2.78
Upthrust = weight of water displaced = 5.0 − 3.2 = 1.8 N. Relative density = weight in air ÷ upthrust = 5.0 ÷ 1.8 = 2.78. 1.56 divides by the apparent weight instead of the loss in weight. 0.36 is the reciprocal. 1.8 is the upthrust in newtons, not a relative density.
eZine practice question (original, teacher-reviewed)
Want more Physics questions, timed, with every mistake explained?
Practise free on eZine →Topics in eZine's WAEC Physics practice bank
- Motion (45)
- Light waves I (29)
- Electric Field (27)
- Heat Energy Measurements I (17)
- Concept of nuclear energy and its use for generation of electricity (16)
- Gravitational Field (14)
- Particulate Nature of Matter (14)
- Electro-magnetic Field (13)
- Fundamental and Derived Quantities and Units (13)
- Introductory electronics (13)
- Concept and properties of light II (12)
- Equilibrium of Forces II (12)
- Work, Energy and power (12)
- Elasticity (11)
- Equilibrium of Forces I (11)
- Heat Energy (11)
- Magnetic field (11)
- Concept and properties of light I (10)
- Gas Laws (9)
- Electric charge (8)
- Quantities and Measurements (8)
- Fluids at rest and in motion (7)
- Heat Energy: Temperature and its measurement I (7)
- Application of Sound Waves (6)
Published questions per topic, counted 29 October 2026. eZine does not reproduce WAEC's own Physics syllabus here; check the official syllabus with your school or at the WAEC website.