Today’s activity is all about ramps, gradients and friction. We’re going to investigate how the distance travelled by a car is affected by the gradient of the slope and the surface of the ramp.

Materials

A ramp – we used this brilliant ramp from The Consortium, but you could make your own with cardboard or wood.

Carpet or other rough surface.

Cars – LEGO or DUPLO work well.

Chalk

Tape measure

We’re investigating two different things in this activity, so need to be very careful to only test one at a time and keep the other variables constant.

Do not push the car, just let it go without any force behind it.

### How does gradient affect distance travelled?

Things to keep constant

Use the same car and the same ramp.

Record the distance travelled using chalk by the car for three different gradients, what do you notice?

### How does the surface of the ramp affect distance travelled?

Keep the car and gradient constant this time, but record the distance travelled using a smooth and a rough surface on your ramp. What do you notice?

Gathering data

We repeated each test 3 times and found the average distance travelled by the cars then recorded the data in a table.

Results

Cars travelled further if the gradient was steeper, this is because a steeper gradient allows the car to pick up more speed.

Our cars travelled less far when we used the carpet surface than when we used the smooth surface. This is because there is more friction between the car and carpet than between the car and smooth surface.

For younger children

Try pushing the car and comparing with the distance travelled if you don’t push. Does the extra force make a difference?

Friction Ramp from The Consortium

The friction ramp we used in this activity is one of my favourite resources we’ve been lucky enough to try out so far. It is beautifully made, very sturdy and I know is something we’ll use for many years to come. The ramp has three different surfaces to test, one smooth, one carpet and one slightly rough. It also comes with a truck that you can add weight to, which we haven’t used yet. I’m very much looking forward to thinking of more creative ways to use it.

Extension Activities

Is there a point where a steeper gradient makes the distance travelled smaller?

What happens if you change the surface at the bottom of the ramp?

What happens if you make the cars heavier?

Suitable for Key Stage 2

Forces and Magnets

Compare how things move on different surfaces

Working Scientifically