Free Force and Motion MCQs with Answers
1,416 Force and Motion MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Displacement, velocity and acceleration describe motion, including the horizontal and vertical components of projectile motion. The chapter connects these quantities with Newton's laws, momentum and impulse, then applies conservation of momentum to collisions, distinguishing elastic collisions from inelastic ones.
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- A. 1 m per second
- B. 1.5 m per second
- C. 0.5 m per second
- D. 3 m per second
Explanation: Total momentum before is 2 multiplied by 3, that is 6 kg m per second, and the combined mass afterwards is 6 kg, so the common velocity is…
Correct answer: 1 m per second- A. they stick together
- B. the moving body stops and the stationary one moves off with the original velocity
- C. both move off at half the original velocity
- D. the moving body rebounds
Explanation: Conserving both momentum and kinetic energy for equal masses gives a complete exchange of velocities, which is what makes the Newton's…
Correct answer: the moving body stops and the stationary one moves off with the original velocity- A. 30 degrees
- B. 45 degrees
- C. 60 degrees
- D. 90 degrees
Explanation: Range is proportional to sin 2 theta, which is maximum when 2 theta is 90 degrees, that is at 45 degrees, assuming level ground and no air…
Correct answer: 45 degrees- A. increases steadily
- B. decreases steadily
- C. stays constant, because no horizontal force acts
- D. becomes zero at the highest point
Explanation: Gravity acts vertically only, so the horizontal motion is uniform while the vertical motion is uniformly accelerated, and treating the two…
Correct answer: stays constant, because no horizontal force acts- A. 15 m
- B. 30 m
- C. 45 m
- D. 90 m
Explanation: Using s equals half g t squared, the distance is half multiplied by 10 multiplied by 9, giving 45 m.
Correct answer: 45 m- A. 2 m per second squared
- B. 4 m per second squared
- C. 6 m per second squared
- D. 8 m per second squared
Explanation: Acceleration is the change in velocity divided by the time, so 20 divided by 5 gives 4 m per second squared.
Correct answer: 4 m per second squared- A. is a vector and displacement is a scalar
- B. is the total path length travelled, while displacement is the straight line change in position
- C. is always smaller than displacement
- D. is measured in different units
Explanation: Walking once round a circular track leaves the displacement at zero while the distance equals the circumference, so distance can exceed…
Correct answer: is the total path length travelled, while displacement is the straight line change in position- A. constant velocity
- B. zero acceleration
- C. changing velocity and therefore acceleration
- D. no force acting on it
Explanation: Velocity is a vector, so a continuous change of direction is a change of velocity even at constant speed, and the acceleration points…
Correct answer: changing velocity and therefore acceleration- A. greater than their true weight
- B. less than their true weight
- C. equal to their true weight
- D. zero
Explanation: The floor must both support the weight and supply the extra upward force to accelerate the person, so the normal reaction, which is what…
Correct answer: greater than their true weight- A. the exhaust gases push against the air behind it
- B. the momentum carried away by the exhaust gases is balanced by an equal forward momentum of the rocket
- C. gravity pulls it forward
- D. it becomes lighter as fuel burns
Explanation: Conservation of momentum, equivalently Newton's third law, means expelling mass backwards at speed drives the rocket forwards, and no…
Correct answer: the momentum carried away by the exhaust gases is balanced by an equal forward momentum of the rocket- A. 20 kg m per second
- B. 0.8 kg m per second
- C. 50 kg m per second
- D. 9 kg m per second
Explanation: Momentum is mass multiplied by velocity, so 4 multiplied by 5 gives 20 kg m per second in the direction of motion.
Correct answer: 20 kg m per second- A. the area of contact only
- B. the normal force pressing them together and the nature of the surfaces
- C. the speed only, in all cases
- D. the volume of the bodies
Explanation: Limiting friction is the coefficient of friction multiplied by the normal reaction, and to a good approximation it is independent of the…
Correct answer: the normal force pressing them together and the nature of the surfaces- A. 15 degrees
- B. 30 degrees
- C. 45 degrees
- D. 60 degrees
Explanation: Range is proportional to sin of twice the angle and is greatest at 45 degrees, where sin 90 equals 1, so half the maximum range needs sin…
Correct answer: 15 degrees- A. Equal to initial velocity
- B. Half of initial velocity
- C. Equal to zero
- D. Minimum but not zero
Explanation: At the top the vertical component has fallen to zero, but the horizontal component is unchanged throughout the flight because no…
Correct answer: Minimum but not zero- A. Law of conservation of energy
- B. Backward thrust of the gases
- C. Newton's third law of motion
- D. Newton's first law of motion
Explanation: The cannon pushes the shell forward and the shell pushes the cannon back with an equal and opposite force, which is the third law, and the…
Correct answer: Newton's third law of motion- A. Point of projection
- B. Highest point
- C. Between launching and highest point
- D. At all points
Explanation: The vertical component decreases as the projectile rises and is regained on the way down, so the speed is greatest at launch and again on…
Correct answer: Point of projection- A. 4 m/s
- B. 2 m/s
- C. 6 m/s
- D. Depends on masses
Explanation: For a perfectly elastic collision the relative speed of separation equals the relative speed of approach, whatever the masses, which…
Correct answer: 4 m/s- A. Meter per secound
- B. meter per second square
- C. Both
- D. All
Explanation: Acceleration is change in velocity per unit time, so its SI unit is metre per second squared, written m/s².
Correct answer: meter per second square- A. Variable acceleration
- B. Constant acceleration
- C. Zero acceleration
- D. All of these
Explanation: Acceleration is the slope of a velocity-time graph. A parabolic curve has a changing slope, so the acceleration varies with time; the…
Correct answer: Variable acceleration- A. Speed
- B. Velocity
- C. Acceleration
- D. All of these
Explanation: The slope of a velocity-time graph is change in velocity divided by time, which is acceleration, measured in m/s².
Correct answer: Acceleration