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Bike Shop 3-5 / Week 02 / Friday
5/6
Week 02 · Pushes and Pulls

Friday

Plan a fair push test
// The forces that start, stop and turn a bike
⏱ about 15 min

Friday: Plan a Fair Push Test

Rocket wants to test pushes. He pushes a car on the rug, then a ball on the floor.

"The ball went farther!" he says. "So bigger pushes win!"

Raven tilts her head. "What do you notice? You changed lots of things."

Nova hovers between them. "A fair test changes just one thing," she says. "Which thing will you change?"

Fair tests

Scientists use fair tests to find answers.

In a fair test, you change only one thing.

Everything else stays the same.

For a push test, change only the size of the push.

Use the same toy, the same floor and the same starting line.

Try each push more than once. Then you can trust your results.

IS IT FAIR?
  • Read the question.
  • Tap your answer.
Rocket used a car on the rug and a ball on the floor. Was that fair?
In our push test, which one thing do we change?

Practice results

These are made-up practice numbers, not real results.

A toy car was pushed three times with each size of push.

Push (made-up practice)Try 1Try 2Try 3
small20 cm22 cm21 cm
medium45 cm48 cm46 cm
big80 cm85 cm83 cm
In the practice table, how far did the small push go on try 1? Type the number of cm.
Which push went farthest every time? Type small, medium or big.
About the practice tableTrue or false?
The medium push always went farther than the small push.?
The three tries for each push were exactly the same.?
The big push went about 80 cm or more every time.?
WHY THIS EXERCISETries can differ a little. That is why scientists test more than once.
  1. Pick one toy: a car, ball or can.
  2. Pick one floor and mark a starting line with tape or a sock.
  3. Plan a small push, a medium push and a big push.
  4. Plan to try each push three times.
  5. Draw an empty table in your shop notebook for tomorrow.
Safety first
Test on an open floor, away from stairs and people's feet.
Push gently enough that nothing breaks.
In your shop notebook, draw your test setup. Show the toy, the starting line and the floor.

Excellent planning! Tomorrow is Bike Shop Day: run your push test with your family.

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