Motion, forces and stopping: GCSE Combined Science Physics practice questions

Question 1 Hard

A car starts from rest and accelerates at 2 m/s² over a distance of 25 m. Work out its final speed.

Question 2 Hard

A skydiver opens a parachute and slows to a lower terminal velocity. Explain why.

Question 3 Hard

Explain why doubling the speed of a car more than doubles its braking distance.

Question 4 Hard

A car of mass 1000 kg has a braking force of 5000 N. Work out its deceleration.

Question 5 Easy

A jogger runs at a steady 3 m/s for 50 s. Work out the distance.

Question 6 Easy

A car travels 300 m in 20 s. Work out its average speed.

Question 7 Medium

On a distance-time graph, a straight line goes from 0 m at 0 s to 24 m at 8 s. Work out the speed.

Question 8 Medium

A driver travelling at 25 m/s has a reaction time of 0.6 s. Work out the thinking distance.

Question 9 Hard

A walker covers 90 m in 60 s, then 60 m in 20 s. Work out the average speed for the whole journey.

Question 10 Hard

Higher tier. A velocity-time graph is a straight line from 0 m/s at 0 s to 12 m/s at 6 s. Work out the distance travelled.

Check 1

What is acceleration?

1. How quickly the velocity changes
2. How far an object travels
3. The pull of gravity on an object

Check 2

What is the unit of acceleration?

1. m/s
2. m/s²
3. N

Check 3

What is the equation for acceleration?

1. acceleration = change in velocity × time taken
2. acceleration = velocity + time
3. acceleration = change in velocity ÷ time taken

Check 4

What does a negative acceleration mean?

1. The object is slowing down
2. The object is going backwards
3. The object has stopped

Check 5

A train speeds up from 0 to 30 m/s in 10 s. What is its acceleration?

1. 300 m/s²
2. 3 m/s²
3. 40 m/s²

Check 6

What does the gradient of a speed-time graph show?

1. The distance travelled
2. The time taken
3. The acceleration

Check 7

What does a flat horizontal line on a speed-time graph show?

1. Constant speed
2. The object is speeding up
3. The object is slowing down

Check 8

What is the equation linking force, mass and acceleration?

1. resultant force = mass ÷ acceleration
2. resultant force = mass × acceleration
3. resultant force = mass + acceleration

Check 9

Two objects get the same resultant force. One has a bigger mass. Which accelerates less?

1. The one with the smaller mass
2. They accelerate the same
3. The one with the bigger mass

Check 10

What happens to a moving object if the resultant force is zero?

1. It keeps moving at a constant velocity
2. It slows down and stops
3. It speeds up

Check 11

What is drag?

1. The pull of gravity
2. A force from air or water that opposes the motion
3. The force from a skydiver's parachute only

Check 12

What is terminal velocity?

1. The fastest speed a car can reach
2. The speed when an object lands
3. The constant speed reached when the resultant force is zero (for a falling object, drag equals weight)

Check 13

Why does the drag on a skydiver increase as she speeds up?

1. Faster movement gives more air resistance
2. Her weight increases
3. The air gets thicker

Check 14

At terminal velocity, how does the drag compare with the weight?

1. The drag is bigger
2. They are equal
3. The weight is bigger

Check 15

Why does opening a parachute lower the terminal velocity?

1. It reduces the skydiver's weight
2. It removes the drag
3. It gives more drag at a lower speed

Check 16

What is thinking distance?

1. The distance travelled while the driver reacts
2. The distance travelled while braking
3. The distance to the hazard

Check 17

What is braking distance?

1. The distance travelled while the driver reacts
2. The distance travelled once the brakes are on
3. The total distance of the journey

Check 18

What is the equation for stopping distance?

1. thinking distance × braking distance
2. braking distance − thinking distance
3. thinking distance + braking distance

Check 19

Which makes the thinking distance longer: tiredness, a wet road or worn tyres?

1. Tiredness
2. A wet road
3. Worn tyres

Check 20

Which makes the braking distance longer: alcohol, a wet road or a distraction?

1. Alcohol
2. A wet road
3. A distraction

Check 21

Why does doubling the speed of a car more than double its braking distance?

1. The brakes work half as well
2. The thinking distance doubles
3. The kinetic energy depends on the speed squared

Check 22

When brakes slow a car, which store gains the energy?

1. The thermal store of the brakes
2. The gravitational potential store
3. The elastic potential store

Check 23

A student says: a skydiver at terminal velocity has no forces acting on her. What is wrong?

1. Nothing is wrong
2. Weight and drag still act but they are balanced
3. Only the weight acts

Check 24

Higher tier. In v² − u² = 2as, what does u stand for?

1. The final speed
2. The distance
3. The starting speed

Check 25

Roughly how fast do people walk, run and cycle?

1. Walk 1.5 m/s, run 3 m/s, cycle 6 m/s.
2. Walk 15 m/s, run 30 m/s, cycle 60 m/s.
3. Walk 0.15 m/s, run 0.3 m/s, cycle 0.6 m/s.

Check 26

Roughly what is the speed of sound in air?

1. About 3 m/s
2. About 330 m/s
3. About 300 000 000 m/s

Check 27

What is the equation linking distance, speed and time?

1. distance = speed ÷ time
2. distance = time ÷ speed
3. distance = speed × time

Check 28

How do you calculate average speed?

1. Total distance ÷ total time
2. Add the highest and lowest speed and halve it.
3. Total time ÷ total distance

Check 29

What does the gradient of a distance-time graph show?

1. The distance travelled
2. The speed
3. The acceleration

Check 30

What does a flat line on a distance-time graph show?

1. The object is stationary.
2. The object is moving at a steady speed.
3. The object is accelerating.

Check 31

What is the difference between speed and velocity?

1. Speed has a direction. Velocity does not.
2. They are the same thing.
3. Velocity has a direction. Speed does not.

Check 32

Higher tier. How do you find the speed at one moment from a curved distance-time graph?

1. Draw a tangent and find its gradient.
2. Read the height of the curve.
3. Find the area under the curve.

Check 33

Higher tier. What does the area under a velocity-time graph show?

1. The acceleration
2. The distance travelled
3. The final velocity

Check 34

Higher tier. A car goes round a roundabout at a constant 10 m/s. Is its velocity constant?

1. Yes, because the speed is constant.
2. Yes, because there is no force on the car.
3. No, because the direction keeps changing.

Check 35

What acceleration does a freely falling object have near the Earth's surface?

1. About 9.8 m/s²
2. About 98 m/s²
3. About 0.98 m/s²

Check 36

What is the typical range of human reaction times?

1. About 0.002 s to 0.009 s
2. About 0.2 s to 0.9 s
3. About 2 s to 9 s

Check 37

How can you measure reaction time with a ruler?

1. Catch a dropped ruler and measure how far it fell.
2. Time how long a ruler takes to fall to the floor.
3. Measure how long the ruler is.

Check 38

Why can a very large deceleration be dangerous?

1. The car gains kinetic energy.
2. The thinking distance gets longer.
3. The brakes can overheat and control can be lost.