Outcomes

Pupils can interpret velocity-time graphs including zero velocity, constant speed, constant acceleration, constant deceleration and have an appreciation for changing acceleration and negative velocity.
Pupils should be able to sketch a velocity-time graph from a distance-time graph. They should be able to pin point key areas starting with zero velocity regions.
Pupils should be able to calculate the gradient of a distance-time graph to work out the speed in order to add a scale to a sketched velocity-time graph.
Pupils should be able to calculate the gradient of a velocity-time graph to work out the acceleration. They should appreciate that the shape of velocity time graphs indicate if the acceleration is zero, constant or changing.
Pupils should understand that the area under a velocity time graph gives the distance travelled.

Specification References

1.5 interpret velocity-time graphs
1.6 determine acceleration from the gradient of a velocity-time graph
1.7 determine the distance travelled from the area between a velocity-time graph and the time axis.

Using a motion sensor and Making Velocity-time Graphs
The pupils extend the exercise from the previous lesson but now try and produce velocity time graphs and linking them back to the distance time graphs. Ask them to cut out and match up the velocity-time graphs with the distance-time graphs from the previous lesson.

Using The Journey again have the pupils use the last column of the table to work out the instantaneous speed at each step of the train journey. They should do this in groups so that they share out the work between four. This should make this go a bit quicker. From this they make the connection between constant slope being constant speed and horizontal portions being zero speed. Hand out The Journey - sketching velocity-time graphs. This allows pupils to sketch the velocity time graph below the distance time graphs with the time scale in-line. They can use their calculations from earlier to help add values to the y-axis. You can spend time pointing out the key points (horizontal->zero gradient->zero speed, constant slope-> constant gradient-> constant speed, changing slope-> changing gradient-> changing speed-> acceleration, steeper slope-> larger gradient-> greater speed)
Have the students work out the area of the By Train velocity-time graph. This may require some estimating. What does this represent? Hopefully they will make the connection that the area under a velocity-time graph is the distance travelled. Look back at the data. How far does the train travel? Have them look at the units when they multiply the velocity and the time axis. It is important for them to see that the time unit cancels and they are left with metres.
Finish with two or three example questions. These start easy and lead into negative velocity and objects travelling back home.

Risk Assessment