Have you seen real racecars stop in the pit to change tires when they wear out? Here’s a short video showing everything they do when the car does a pit stop!
Our Lego tires don’t wear out, but let’s make a pit stop to change the SIZE of tires. Your LEGO set has large and small tires. Whichever ones you built with, switch them for the other size.
Now re-run your trials. At the same speed and power, how far does the car go with different sized tires? Here’s the chart from the last page:
Power
Seconds
How Far?
8
2
_______
4
2
_______
4
6
_______
Modifications
Take the blue disk off of the motor. Replace it with a small yellow donut (called a bushing). Put the red band back on.
Now re-run your trials. At the same speed and power, how far does the car go with the yellow bushing?
Power
Seconds
How Far?
8
2
_______
4
2
_______
4
6
_______
Switch the yellow bushing and the blue disk on the axle, so that the yellow bushing is on the axle and the blue disk is on the motor. Run the time trial one more time!
Power
Seconds
How Far?
8
2
_______
4
2
_______
4
6
_______
Which arrangement would you recommend for a fast racecar?
