Lesson 49 of 84 · Forces
Lesson⭐ 30 XP⚡ Spark LabBalanced and Unbalanced Forces (Part 2)
Balanced and Unbalanced Forces (Part 2).
🎯 Your mission
Understand the idea. Then look for it everywhere.
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Before you start: which will move faster, and why?
What You'll Learn
Balanced forces are equal in size and opposite in direction, so an object stays still or moves at constant speed. Unbalanced forces cause an object to accelerate or change direction.
Key Words
- potential
- work
- power
Steps
Read the introduction and identify the main idea of this lesson.
Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.
Look for patterns in your observations.
Make a graph or chart showing your results.
Check Your Understanding
Question 1
1 of 3What do balanced forces result in?
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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