All Free Physics MCQs with Answers
Every Physics question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
13,934 questions · page 1 of 697
- A. Joule
- B. Watt
- C. Newton
- D. Pascal
Explanation: The SI unit of force is the newton (N), defined as the force that accelerates a one-kilogram mass at one metre per second squared.
Correct answer: Newton- A. 3 × 10⁶ m/s
- B. 3 × 10⁸ m/s
- C. 3 × 10¹⁰ m/s
- D. 3 × 10⁵ m/s
Explanation: Light travels at approximately 3 × 10⁸ metres per second in a vacuum — about 300,000 kilometres per second.
Correct answer: 3 × 10⁸ m/s- A. force equals mass times velocity
- B. force equals the rate of change of momentum
- C. force equals mass times distance
- D. force equals momentum times time
Explanation: The general statement is that the net force equals the rate of change of momentum, which reduces to F equal to ma only when the mass is…
Correct answer: force equals the rate of change of momentum- A. a net force acting on it in the direction of motion
- B. zero net force acting on it
- C. a net force acting opposite to its motion
- D. an increasing acceleration
Explanation: Uniform velocity means zero acceleration, and by Newton's second law zero acceleration requires zero net force.
Correct answer: zero net force acting on it- A. 0.2 m s-2
- B. 5 m s-2
- C. 16 m s-2
- D. 80 m s-2
Explanation: From F equal to ma, the acceleration is 20 divided by 4, which is 5 m s-2.
Correct answer: 5 m s-2- A. act on the same body and cancel out
- B. act on different bodies and therefore never cancel
- C. are unequal in magnitude
- D. act in the same direction
Explanation: The pair is equal in magnitude and opposite in direction but acts on two different bodies, which is why they cannot cancel each other and…
Correct answer: act on different bodies and therefore never cancel- A. 30 degrees
- B. 45 degrees
- C. 60 degrees
- D. 90 degrees
Explanation: Range is proportional to sine of twice the launch angle, which is largest when twice the angle is 90 degrees, so the angle itself is 45…
Correct answer: 45 degrees- A. zero in every direction
- B. horizontal only, with the vertical component zero
- C. vertical only
- D. equal to the launch velocity
Explanation: Gravity acts only vertically, so the horizontal component of velocity is unchanged throughout the flight while the vertical component…
Correct answer: horizontal only, with the vertical component zero- A. Speed
- B. Distance
- C. Displacement
- D. Time
Explanation: Displacement has both magnitude and direction, whereas distance records only how far was travelled with no direction attached.
Correct answer: Displacement- A. N s-1
- B. kg m s-1
- C. kg m s-2
- D. N m
Explanation: Momentum is mass times velocity, so its unit is kilogram metre per second.
Correct answer: kg m s-1- A. 0.5 m s-1
- B. 1 m s-1
- C. 1.5 m s-1
- D. 2 m s-1
Explanation: Momentum is conserved, so the initial momentum of 2 times 3, which is 6 kg m s-1, is shared by the combined mass of 6 kg, giving a…
Correct answer: 1 m s-1- A. Kinetic energy
- B. Mass alone
- C. Velocity of each body
- D. Potential energy
Explanation: An elastic collision is defined by the conservation of kinetic energy as well as momentum, and collisions between gas molecules are…
Correct answer: Kinetic energy- A. 40 m
- B. 80 m
- C. 160 m
- D. 320 m
Explanation: With uniform acceleration from rest the average velocity is half the final velocity, which is 10 m s-1, and over 8 s that gives 80 m.
Correct answer: 80 m- A. acceleration
- B. displacement
- C. force
- D. momentum
Explanation: Multiplying velocity by time gives displacement, so the area enclosed between the curve and the time axis is the displacement travelled.
Correct answer: displacement- A. 0 degrees
- B. 45 degrees
- C. 90 degrees
- D. 180 degrees
Explanation: Work is the scalar product Fd cos theta, and cos 90 degrees is zero, so a force perpendicular to the displacement does no work.
Correct answer: 90 degrees- A. equal to mgh
- B. zero
- C. equal to the weight times the distance walked
- D. negative
Explanation: The upward force supporting the suitcase is perpendicular to the horizontal displacement, so the work done against gravity is zero.
Correct answer: zero- A. mass is halved
- B. speed is doubled
- C. speed is increased by a factor of the square root of two
- D. mass is doubled and speed halved
Explanation: Kinetic energy is half m v squared, so it scales with the square of the speed.
Correct answer: speed is increased by a factor of the square root of two- A. 10 J
- B. 20 J
- C. 40 J
- D. 80 J
Explanation: Kinetic energy is half times 5 times 4 squared, which is half times 5 times 16, giving 40 J.
Correct answer: 40 J- A. its total mechanical energy
- B. the change in its kinetic energy
- C. the change in its potential energy
- D. its momentum
Explanation: The work-energy theorem equates net work with the change in kinetic energy, which is why a braking force doing negative work brings a car…
Correct answer: the change in its kinetic energy- A. the total work done
- B. the rate of doing work
- C. work done times time taken
- D. force times displacement
Explanation: Power is work done per unit time, measured in watts, where one watt is one joule per second.
Correct answer: the rate of doing work