The overall effect of a set of forces acting on an object.

A measurement of how fast something is moving, found from the distance travelled divided by the time taken.

A small wheeled cart used in motion experiments.

Changing speed

Science

In the Measuring and calculating motion unit, they will build on this knowledge to learn how to measure and calculate velocity and acceleration, and how to interpret velocity-time graphs. 

In the Forces unit, pupils learn to accurately describe and explain the actions of forces in a range of situations. 

Moving by force

Physical activity and equipment requiring safe use

The sum of forces on an object, accounting for direction.

A wheeled device used in motion experiments.

Moving at constant speed in one direction.

A person drags a box along the ground using a force of 25 N towards the right. A frictional force of 20 N acts on the box as it is dragged. What is the resultant force on the box?

The sprinter is at the same speed throughout the race as the force is constant.

The sprinter's speed will only increase at the start of the race.

The sprinter's speed will change as long as there is a resultant force acting.

The sprinter produces a forwards force only at the start of the race.

The forces on the sprinter are always balanced so the speed stays constant.

A sprinter takes part in a 100 m race. Which statement describes how the forces change during the race?

There is a resultant force in the same direction as the car's movement.

There is a resultant force in the opposite direction to the car's movement.

The figure shows a distance-time graph for a car. What does the graph show?

The rocket will accelerate upwards for the first 5 s.

After 5 s the speed of the rocket will start to decrease.

After 5 s the rocket will start to move downwards.

The rocket's speed will still be increasing after 5 s.

A firework rocket is launched vertically and it produces a large thrust for 5 s then the fuel runs out. Which answers correctly describe the rocket's motion?

What feature of a distance-time graphs shows the speed?

Has a special colour for each type of force.

Starts at the point where the force acts.

Which of these show how forces should be represented on diagram?

A driving force keeping the trolley moving.

A normal contact force due to the ground.

Ben pushes a shopping trolley so it is moving quickly but then falls and lets go. Which of these forces still act on the trolley after he has let go?

The time for the trolley to pass between the markers.

The time the trolley took to reach the markers.

A student is measuring the average speed of a trolley between two points marked on a ramp. Which measurements do they need to make to find the speed?

What is the average speed of this object?

Content guidance

Risk assessment required - equipment

Adult supervision required

This lesson will soon be taken down.

Changing speed

Lesson outcome

Content guidance