Lesson 7 of 8 · Thermodynamics
Lesson⭐ 30 XPThe First Law and Why Perpetual Motion Fails
Thermodynamics.
🎯 Your mission
Understand the idea. Then look for it everywhere.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
The first law of thermodynamics is conservation of energy applied to heat and work: the change in internal energy equals heat added minus work done by the system. No machine can output more energy than it takes in, which rules out perpetual motion of the first kind.
Key Words
Tap a word to see its definition.
Steps
Read the explanation above and note the two key terms before you start.
Research two historical perpetual-motion designs, sketch each, and write one paragraph per design identifying exactly which energy transfer its inventor failed to account for.
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 2The first law of thermodynamics is a statement of:
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
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The First Law and Why Perpetual Motion Fails
Understand the idea. Then look for it everywhere.
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