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Science Launch G4 / Week 01 / Wednesday
3/6
Week 01 · Speed and Energy

Wednesday

Investigation: Ramp race
// Faster things carry more energy
⏱ about 15 min

Wednesday: Ramp race

Rocket props a long piece of cardboard on a stack of books. "A ramp!" he says. "Let's build it!"

He grabs a marble and pushes it hard down the slope.

Raven holds up a hand. "Wait. If you push it, we cannot tell what the ramp did. What do you notice about a fair test?"

Nova blinks. "Would you like a hint? Change only one thing at a time. Keep everything else the same."

Rocket grins. "Then I will just let go. No pushing."

What you need

  • A stiff piece of cardboard, about as long as your arm
  • Three or four thick books
  • A marble or a small ball
  • A paper cup
  • A ruler or a tape measure
  • Tape
Safety first
A grown-up cuts a small doorway in the rim of the cup with scissors.
Keep marbles away from little brothers and sisters.
Nothing goes in your mouth.
Roll the marble on the floor, not toward people.

Steps

  1. Stack one book. Lean the cardboard on it to make a ramp.
  2. Tape the ramp so it does not slide.
  3. Set the cup upside down at the bottom, doorway facing the ramp.
  4. Hold the marble at the top of the ramp. Let go without pushing.
  5. Measure how far the cup slides in centimeters.
  6. Do it two more times. Write each number in the table.
  7. Now stack three books and do the same three tries.
MAKE A PREDICTION
  • Read the question.
  • Tap your answer.
On the higher ramp, the marble will be moving faster at the bottom. What will the cup do?
RampTry 1 (cm)Try 2 (cm)Try 3 (cm)
One book
Three books
What one thing did we change on purpose? The ____ of the ramp.
Did you push the marble or just let go? Write push or let go.

Why three tries?

Your three numbers for one ramp were probably close, but not exactly the same.

Small things change each time, like where the cup sits or how you let go.

Doing three tries helps you see the real pattern instead of one lucky result.

CHECK YOUR THINKING
  • Read the question.
  • Tap your answer.
Why did we let go of the marble instead of pushing it?
Your one book tries were 7, 8 and 8 centimeters. What is a fair summary?
Fair test ruleGood rule?
Use the same marble for every try?
Push the marble harder on the high ramp?
Keep the cup in the same spot each time?
WHY THIS EXERCISEKeeping everything else the same makes the test fair.

You ran a real fair test today. Scientists do three tries because results wiggle a little. Tomorrow we read the evidence.

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