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Waterskiing by Kelley and Matt

We ride the waves all summer long on wakeboards, water skis, and on bare feet. But, performing a good trick isn't just skill. It also depends on our driver pulling us at the right speed. How do different boat speeds affect our waterskiing tricks?

What did we do?
We each chose four different tricks to test. We performed each stunt twice at slow, medium and fast speeds. Then we played judge and rated each other's performances on a 1-5 style scale. We also wrote down any notes we had about the trick. Here's how Kelly scored:

  Slow Speed Medium Speed Fast Speed
Style Notes Style Notes Style Notes
Trick 1 3 lean back 4 upright 2 lean forward
Trick 2 3 lean back 5 perfect! 3 wipe out
Trick 3 3 lean back 4 good 2 wipe out
Trick 4 3 lean back 5 aced it! 2 wipe out

What did we find out?
After tons of action and even more wipeouts, we figured out that you definitely need different speeds for different tricks. Faster isn't necessarily better for every trick. Kelley performed her tricks at a speed of 14 mph. When she went any faster than that, she lost control. Any slower than 14 mph made her ski plow too deep in the water. I needed a speed of 18 mph to do my best performance.

What can you do?
  • Use science to help you improve your performance in your favorite sport. Do you skateboard? How does the size of the board affect your ability to do tricks? Design an investigation to figure out which skateboard features are best for certain stunts.
  • Snowboarders and skiers use wax to improve their glide. But too much wax can actually slow you down. Make up an investigation to find out how the type, amount and location of your wax affects your performance.
  • Use this physics investigation as a science fair project idea for your elementary or middle school science fair! Then tell us about it!
more resources
More on Newton's Laws

Go to the DFTV Boards, and tell us about your science investigation.
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