Lesson 8 of 12 · Momentum
Lesson⭐ 30 XPMomentum and Newton's Second Law
Momentum and Newton's Second Law.
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ 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
Newton actually stated his second law as force equals rate of change of momentum, F = Δp/Δt. For constant mass this simplifies to F = ma, but the momentum form still works when mass changes — for a rocket burning fuel, or a conveyor being loaded.
Key Words
Tap a word to see its definition.
Steps
Read the explanation above and note the two key terms before you start.
Work through two calculations: a 0.15 kg ball struck from rest to 30 m/s in 5 ms, and sand falling onto a belt at 3 kg/s at 4 m/s. Find the force in each case and identify which one F = ma cannot handle.
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 2Newton's second law in momentum form is:
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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Momentum and Newton's Second Law
Master the concept. Use it tomorrow.
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