Lesson 2 of 10 · Energy
Experiment⭐ 30 XP⚡ Spark LabKinetic Energy Grows With the Square of Speed
Kinetic Energy Grows With the Square of Speed.
🎯 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
Kinetic energy is ½mv². Because speed is squared, doubling a car's speed quadruples its kinetic energy — and roughly quadruples its braking distance. That single relationship is the physics behind most speed limits.
Key Words
Tap a word to see its definition.
Materials Needed
- trolley
- foam blocks
- ramp
- metre rule
- stopwatch
Safety First
- Keep hands out of the crush zone during each run.
Steps
Read the explanation above and note the two key terms before you start.
Roll a trolley into a foam barrier at three measured speeds and record the crush depth each time. Plot crush depth against speed and then against speed squared, and identify which gives the straighter line.
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 2A car doubles its speed. Its kinetic energy becomes:
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.”
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Kinetic Energy Grows With the Square of Speed
Predict it first. Then prove yourself right (or wrong).
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