Lesson 49 of 84 · Forces
Experiment⭐ 30 XP⚡ Spark LabBalanced and Unbalanced Forces (Part 2)
Balanced and Unbalanced Forces (Part 2).
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ 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
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
- simple machine
- lever
- pulley
Materials Needed
- blocks
- spring scale
- stopwatch
- pencils
- toy cars
- ramps
Safety First
- Adult supervision recommended.
- Do not taste any materials.
- Wear safety goggles when mixing liquids.
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
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
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