Lesson 21 of 84 · Forces
Experiment⭐ 30 XP⚡ Spark LabHow Machines Help Us
How Machines Help Us.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Predict: what happens if you double the force?
What You'll Learn
A force is a push or pull that can change an object's motion, shape, or direction. Forces are measured in Newtons and can act through contact or at a distance.
Key Words
- power
- simple machine
Materials Needed
- stopwatch
- pencils
- toy cars
- ramps
Safety First
- Do not mix unknown chemicals together.
- Tie back long hair before starting the experiment.
Steps
Read about Forces and write down three key facts.
Set up a pendulum with string and a washer. Change the string length and count swings per minute for each. Graph your results.
Note any unexpected results and think about why they happened.
Share your findings with the class or a partner and discuss what you learned.
Check Your Understanding
Question 1
1 of 3Which is an example of potential energy?
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.”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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