Lesson 33 of 84 · Forces
Lesson⭐ 30 XP⚡ Spark LabNewton's Second Law: Force and Acceleration (Part 2)
Newton's Second Law: Force and Acceleration (Part 2).
🎯 Your mission
Understand the idea. Then look for it everywhere.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Guess: where does the energy go?
What You'll Learn
Newton's second law says that force equals mass times acceleration (F = ma). A heavier object needs more force to accelerate at the same rate as a lighter one.
Key Words
- gravity
- friction
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.
Watch carefully for any changes and note the time.
Create a data table to organize your measurements.
Check Your Understanding
Question 1
1 of 3What unit is force measured in?
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.
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