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Everyday Machines / Week 01 / Thursday
4/6
Week 01 · Machines Everywhere

Thursday

Test it: roll or slide?
// What a machine is, and the wheels all around you
⏱ about 15 min

Thursday: Test It, Roll or Slide?

Rocket lines up two toy cars at a start line.

One sits on its wheels. One lies on its side.

"Same push for each one!" Rocket says.

Raven marks where each car stops with tape.

"What do you notice?" she asks.

Nova blinks. "Would you like a hint? Compare the two marks."

A fair test

A fair test changes only one thing.

Today we change how the car sits: wheels or side.

Everything else stays the same.

Same car, same push, same floor.

You need

  • Two toy cars the same size, or one car used twice
  • A smooth floor or a table
  • Tape or a crayon to mark where it stops
Safety first
Push gently with one finger.
Keep the cars on the floor, not near stairs.
Pick up every car and piece of tape when you finish.
  1. Put the car on its wheels at the start.
  2. Give it one gentle push.
  3. Mark where it stops.
  4. Put the car on its side at the start.
  5. Give it the same gentle push. Mark the stop.
  6. Try each way three times.
TryOn wheels: how far?On its side: how far?
1
2
3
For a grown-up
Help keep the push the same each time.
Measure with a ruler or count floor tiles.
WHAT HAPPENED?
  • Read the question.
  • Tap your answer.
Which car went farther in most tries?
What did we change in this test?
Why do we try three times?
Is a hard push and a soft push a fair test?
SentenceTrue or false?
A fair test changes only one thing.?
We pushed the side car much harder.?
The wheels let the car roll farther.?
We used the same floor for both cars.?
WHY THIS EXERCISEA fair test makes the result trustworthy.
Draw your start line and where each car stopped.
OUR FAIR TEST
  • Tap a card.
  • Then tap its spot.
1First
2Next
3Then
4Last

You ran a fair test. That is real science!

Tomorrow you explain the wheel and axle in your own words.

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