With some toy cars and a few simple, inexpensive materials, you can build ramps and incline tunnels with your kids to study the effects of incline on velocity.
Ramps can be constructed with rain gutters (which you can pick up from any home supply store for about $5), cardboard mailing tubes, or paper towel tube rolls that have been cut in half length-wise. Pool noodles can also work with the smallest toy cars or, if they are too narrow, you can use marbles, instead of cars.
Create at least two ramps of the same length. First, give your child some time to set up the ramps and race cars down.
Then, ask, “What do you think will happen if one of the ramps is higher?” Try to race two of the same type of car to see which goes faster. Try the experiment again with two different heights. How does the height of the ramp affect the speed of the toy car?
If you have a stop watch, you can try timing the cars as they roll down the ramps. Record your results in a chart that compares the height of the ramp to the time it takes the car to roll down the ramp.
Explain to older kids that the height of the ramp produces the steepness of the incline, which in turn increases the velocity. Provide older children with a protractor for measuring the angle. Add a new column to your chart and ask them how height, angle, and velocity are related. You can even plot a graph with your results to show the relationship between the angle of the ramp and the speed of the car.
You might also ask kids what else might affect the speed of the car. For example: the material of the ramp, speed bumps, wetting down or oiling up the ramp if the material allows (this won’t work well on cardboard). This introduces the concept of resistance.
Younger kids will experiment to see that the steeper ramps make for speedier cars while older kids will begin to grasp the relationships between incline, resistance, and velocity. And everyone will have fun racing
Extra credit: Create a loop de loop with your cardboard tubes or purchase one made for use with toy cars. Do you have to race the car slower or faster for it to get through the loop without falling? Why is that?
How do you take advantage of your child’s car collection to build math skills?