Lesson 8 of 10 · Energy
Experiment⭐ 30 XP⚡ Spark LabElastic Potential Energy
Elastic Potential Energy.
🎯 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
A stretched or compressed spring stores elastic potential energy equal to ½kx² below its elastic limit. Because extension is squared, stretching a bow twice as far stores four times the energy — which is why draw length matters so much in archery.
Key Words
Tap a word to see its definition.
Materials Needed
- spring
- slotted masses
- clamp stand
- metre rule
- graph paper
Safety First
- Wear eye protection — an overstretched spring can snap back.
- Weight the stand base and keep feet from under the load.
Steps
Read the explanation above and note the two key terms before you start.
Load a spring in steps and record extension. Plot force against extension and find the stored energy as the area under the line for three different extensions. Check that doubling extension quadruples the area.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2Doubling a spring's extension changes the stored energy by a factor of:
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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Elastic Potential Energy
Predict it first. Then prove yourself right (or wrong).
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