Lesson 11 of 12 · Forces
Experiment⭐ 30 XP⚡ Spark LabResolving Forces on a Slope
Resolving Forces on a Slope.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Before you start: which will move faster, and why?
What You'll Learn
A weight on a slope can be split into a component down the slope, mg sin θ, and one into the slope, mg cos θ. That is why a steeper ramp needs more force to hold a trolley still, and why the normal force falls as the angle rises.
Key Words
Tap a word to see its definition.
Materials Needed
- ramp
- trolley
- newton meter
- protractor
Safety First
- Have a partner block the ramp foot so the trolley cannot run off.
Steps
Read the explanation above and note the two key terms before you start.
Hold a trolley stationary on a ramp with a newton meter parallel to the slope, at 10°, 20° and 30°. Compare each reading with mg sin θ calculated from the trolley's weight.
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 component of weight down a slope of angle θ is:
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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Resolving Forces on a Slope
Set it up. Test it. Be amazed.
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