Lesson 18 of 84 · Forces and Motion
Experiment⭐ 30 XP⚡ Spark LabBalanced and Unbalanced Forces
Forces and Motion.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Predict: what happens if you double the force?
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
- string
- weights
- tape
Safety First
- Be careful with scissors — ask an adult for help if needed.
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.”
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