What does fast mean? The same distance in a shorter time, or a longer distance in the same time. Speed is that, made into a single number.
The sports-day race: who was faster?
A board to adjust
Set the two runners' times for 50 m and press Start.
How long does it take to get to school by bicycle?
A board to adjust
Set the distance and change the way of travelling.
Can a moving car stop suddenly?
A board to adjust
A ball rolled out and a child ran after it. Change the speed of the car.
From here speed becomes a graph
What comes next in middle school · motion and energy
The area under the graph
It is the car from above. Draw speed against time as a line, and the area under the line is the distance travelled. You can also see here why the stopping distance becomes four times as long.
The car from above
A board to run
Twenty seconds of setting off, driving and stopping. Watch the area being shaded.
