Lesson 1 of 12 · Forces
Experiment⭐ 30 XP⚡ Spark LabNewton's First Law and Inertia
Newton's First Law and Inertia.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Predict: what happens if you double the force?
What You'll Learn
An object stays at rest, or keeps moving in a straight line at constant velocity, unless a resultant force acts on it. Inertia is the name for that reluctance to change motion, and it scales with mass.
Key Words
Tap a word to see its definition.
Materials Needed
- coins
- ruler
- index card
- beaker or cup
Safety First
- Flick away from faces and keep the coins over a table so they do not fly.
Steps
Read the explanation above and note the two key terms before you start.
Stack five coins and flick the bottom one out sideways with a ruler. The stack drops in place because nothing pushed it sideways. Repeat with a card and coin over a beaker to show the same effect vertically.
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 first law says an object keeps moving at constant velocity unless:
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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Newton's First Law and Inertia
Predict it first. Then prove yourself right (or wrong).
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