The displacement of an object is the distance travelled in a particular direction from a starting point.

A vector is a quantity with magnitude (size) and direction. Displacement and velocity are both vector quantities.

The velocity of an object is its speed in a particular direction.

A centripetal force acts towards the centre of a circle and causes object to travel in circular paths.

Displacement and velocity as vectors: including circular motion

Combined science

In the Energy of moving objects unit, they will build on this knowledge to learn how to calculate the amount of energy of objects have because they are moving, stretched or in a gravitational field; and to calculate energy transfers using knowledge of energy conservation and dissipation.

In the Moving by force unit, pupils learnt how to calculate speed and describe motion using distance-time graphs, apply Newton’s First Law of motion and calculate the amount of energy needed to move an object to a new position.

Measuring and calculating motion

the distance travelled in a straight line from a starting point

a quantity with a magnitude (size) and a direction

a quantity with a magnitude (size) but not a direction

the speed of an object in a particular direction

a force that causes an object to travel in circle

Match the key word with the correct description.

Which of these are examples of displacements?

A train takes 2 hours to travel from one station to another which is 150 km west of the starting point.
Calculate the velocity of the train.

A pupil walks 5 m north, 3 m south and then 2 m north.
Which of these statements about the pupil's journey are correct?

The ball has a constant instantaneous velocity of 4 m/s.

The ball has a constant instantaneous speed of 4 m/s.

The average velocity for one complete revolution is 0 m/s.

A force is acting on the ball directed away from the centre of the circle.

A force is acting on the ball directed towards the centre of the circle.

A ball on the end of a piece of string is spun in a circle so that it travels at 4 m/s. 
Which of these statements are correct?

A pupil walks 10 m west in 10 s, then 5 m east in 5 s and then 15 m west in 25 s.
Calculate the magnitude of the average velocity for the complete journey (do not give the direction).

A pupil measures the time taken for different sports balls to travel 30 cm.
Use the times to put the balls in order of decreasing speed, starting with the fastest.   

average speed = distance travelled ÷ time taken

average speed = distance travelled × time taken

distance travelled = average speed × time taken

time taken = distance travelled ÷ average speed

Which three of these equations show the correct relationship between average speed, distance travelled and time taken?

Change the value of the anomalous result to match the others in the set.

Repeat the test for the anomalous result and replace it with the new value.

Repeat the experiment from the start using different equipment.

Cross out the result and ignore it in any calculations.

Use the result in the calculations but not in the graph.

What should be done with a single anomalous result in a set of five readings?

A pupil measures the time it takes a car to pass between two street lamps as 5.0 s. 
If the car is moving at 8.0 m/s how far apart are the lamps?

A quantity that has magnitude but no direction.

A quantity that has magnitude and direction.

Which of these is a definition of a scalar quantity?

The average speed of the ball was 10 m/s.

The instantaneous speed of the ball was the same throughout the fall.

The highest instantaneous speed of the ball was 10 m/s

The highest instantaneous speed of the ball was less than 10 m/s

The highest instantaneous speed of the ball was more than 10 m/s

A tennis ball is released from a height of 20 m and it falls to the ground, taking 2.0 s.
Which statements about the movement are correct?

Exit Quiz