Today from Bedtime Math: Burning Rubber – on the Court

When people drive their cars really fast and then hit the brakes to stop, sometimes the tires "burn rubber:" they get so hot from skidding against the road that they leave soft black rubber streaks on the street. The car has to be going really fast and stop really short, though, to make that happen. So think how crazy it is when a basketball player can do that! During a basketball game last week between the Miami Heat and Golden State Warriors, the famously speedy player LeBron James slipped and fell, but was going so fast that his sneakers actually burned rubber onto the court. The stadium workers can't even scrape the streaks off the floor, so they may be there a while - just like the skid marks on the highway.

Now here's today's math~

Wee ones: If your feet leave 2 skid marks and your car tires leave 4, who made more?

Little kids: If your rollerblades have 4 wheels each and you skid sideways to stop, how many little skid marks do you make if there's 1 streak per wheel?  Bonus: If LeBron's feet are 13 inches long and those skid marks are 11 inches longer than his foot, how long are his skid marks? 

Big kids: If LeBron was running 18 miles per hour and that's 3 times as fast as you can run, how fast are you?  Bonus: Car skid marks can be really long, since it takes time to stop a heavy car. If after it brakes a car skids for 2 seconds at an average speed of 37 feet per second, how long are the skid marks?

Answers:

Wee ones: The car made more marks.

Little kids: 8 skid marks.  Bonus: 24 inches (2 feet).

Big kids: 6 miles per hour.  Bonus: 74 feet.