Lesson 12 of 12 · Forces
Experiment⭐ 30 XP⚡ Spark LabCentre of Mass and Stability
Centre of Mass and Stability.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
⚡ Static electricity is the same physics as lightning, just smaller.
Make a hypothesis first
Guess: where does the energy go?
What You'll Learn
The centre of mass is the point where an object's weight acts. An object topples once a vertical line from its centre of mass falls outside its base. Wide bases and low centres of mass are what make racing cars and bus chassis stable.
Key Words
Tap a word to see its definition.
Materials Needed
- stiff card
- clamp stand
- string
- small mass
- cardboard boxes
Safety First
- Keep the clamp stand base weighted so it cannot fall.
Steps
Read the explanation above and note the two key terms before you start.
Find the centre of mass of an irregular card by hanging it from three different points and marking the plumb line each time. Then tilt a tall box and a short box until each topples and relate the tipping angles to base width and height.
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 2An object topples when the vertical line from its centre of mass:
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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Centre of Mass and Stability
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