How to Track the Speed of a Hot Wheels Car

Clear a straight space of about 5 meters (a little more than 15 feet) on your floor.

Place a stack of four or five thick books at one end of your space. Lean the plank on top of them so it creates a slope.

Lay out the Hot Wheels track in a straight line heading down the slope.

Using tape, mark off 1-meter intervals along the track. Place the marks where they will be visible. If you place the tape on the track itself, make sure it is smooth and doesn't interrupt the car's passage.

Pass out stopwatches and assign volunteers to stand alongside the track. If you have only one stopwatch, then have someone stand at the end of the track. If you can get five watches and five volunteers, have them stand at the 1-meter interval marks along the track.

Place and hold your Hot Wheels car at the top of the slope. When everyone is ready, tell them to start the stopwatches, and release the car. When the car passes each person, he will stop his stopwatch.

Write down all the data from your experiment. You may want to make a chart for this, with distances laid out vertically.

Repeat steps 6 and 7 another two to four more times, so you have a total of three to five data sets. By gathering as much data as you can, you begin to eliminate errors in your testing method.

Take the average times at your various intervals. To get an average, add up the times and divide by the number of trials you ran.

Divide the time measurement by the distance measurement. For example, if your car reached the 5-meter mark within five seconds, your car was traveling at 1 meter per second: 5 meters/5 seconds = 1 meter/second.