Lesson 80 of 84 · Forces
Experiment⭐ 30 XP⚡ Spark LabBalanced and Unbalanced Forces (Part 3)
Balanced and Unbalanced Forces (Part 3).
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Guess: where does the energy go?
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
Materials Needed
- ruler
- cardboard
- marbles
- paper clips
Safety First
- Adult supervision recommended.
- Do not taste any materials.
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.
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Send it to a parent who's looking for a 10-minute kitchen science win.
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