Forces (OCR GCSE Physics A (Gateway)): Exam Questions

Objects can interact in many ways. Pairs of forces arise when objects interact.

Write down one type of force involved when objects interact.

A book rests on a table.

Draw a free body force diagram to show the forces acting on the book.

Use arrows to represent the forces.

A teacher uses an air-track for motion experiments. Using the air-track means that there is no friction between the glider and the air-track.

The teacher places the glider on the horizontal air-track and gives it a small push to start it moving.

Explain the motion of the glider.

A presenter on a car TV programme says: “The car maker has reduced the mass of this car and it now has better acceleration.”

i) Explain why the presenter is correct.

[2]

ii) A car accelerates from 5 m/s to 25 m/s in 4 seconds. Calculate the acceleration of the car.

Use the equation: Acceleration = Change in speed ÷ Time taken

Answer = ............................................ m/s² [3]

Higher Tier Only

A car travels around a circular track at a constant speed.

Explain why it is incorrect to describe the circular motion as having a constant velocity.

Higher Tier Only

A force is required for the car to maintain the circular motion.

Explain why a force is required.

Higher Tier Only

State the direction in which the force acts for objects in circular motion.

Higher Tier Only

State the name of this force for the car on the track.

Higher Tier Only

Three parachutes are used to slow down a spacecraft as it falls through the atmosphere. 

The spacecraft falls at a constant velocity.

State the name of this constant velocity and explain why this velocity stays at a constant value.

Higher Tier Only

Draw a free body diagram for the spacecraft at its terminal velocity.

Higher Tier Only

The same spacecraft falls through the atmosphere in a test run, but only two of its parachutes are working.

Explain how the constant velocity reached by this spacecraft compares with the constant velocity of the spacecraft in part (a).

Higher Tier Only

When the spacecraft is at a velocity less than its terminal velocity, a strong wind blows to the right.

State the direction of the resultant force on the spacecraft.

Higher Tier Only

A free-fall skydiver falls from a plane and reaches terminal velocity after 15 seconds.

Look at the graph of her motion.

Use the graph to find the acceleration at 5 seconds.

Answer = ......................... m/s²

Higher Tier Only

Use the graph to find the distance travelled between 0 and 2.5 seconds.

Answer= ......................... m

Higher Tier Only

A skydiver jumps from an aeroplane, falls towards the ground, opens her parachute and falls safely to Earth.

Look at the graph of the velocity of the skydiver as she falls.

Look at these regions of the graph:

• x

• y

Use ideas about forces to explain the motion during x and y.