Lesson 21 of 84 · Motion and Forces
Lesson⭐ 30 XP⚡ Spark LabHow Machines Help Us
Motion and Forces.
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Before you start: which will move faster, and why?
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
Steps
Read about Motion and 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
You use this every time you flip a light switch, ride a bike, or kick a ball.
Stretch Challenge
Try this in real life this week.
Time how long a small ball rolls down something, then change the slope and try again.
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.
Checkout complete lesson on Motion and Forces for 8th Grade
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