Lesson 3 of 12 · Forces
Experiment⭐ 30 XP⚡ Spark LabNewton's Third Law: Forces Come in Pairs
Newton's Third Law: Forces Come in Pairs.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Guess: where does the energy go?
What You'll Learn
If A pushes B, then B pushes A with an equal force in the opposite direction. The pair always acts on two different objects, which is why they never cancel out — a rocket pushes gas down and the gas pushes the rocket up.
Key Words
Tap a word to see its definition.
Materials Needed
- wheeled chair
- heavy ball
- lighter ball
- clear floor space
Safety First
- Work on a smooth clear floor away from stairs, with a spotter behind the chair.
Steps
Read the explanation above and note the two key terms before you start.
Sit on a wheeled chair holding a heavy ball and throw it forwards. Record which way you move and estimate the ratio of your speed to the ball's from your masses. Repeat with a lighter ball and compare.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2A rocket accelerates upwards because:
Where you see this in real life
This is why airplanes can fly and why rockets reach space.
Stretch Challenge
Try this in real life this week.
This week, find one thing in your house that turns one kind of energy into another.
For the dinner table
“Show me something at home that uses this kind of energy.”
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Newton's Third Law: Forces Come in Pairs
Run the experiment. Find out what really happens.
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