Lesson 4 of 8 · Energy
Experiment⭐ 30 XP⚡ Spark LabPulleys Lift Loads
Pulleys Lift Loads.
🎯 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
A pulley is a grooved wheel that holds a rope and lets you change the direction of a force. Pulling down on one side lifts a load on the other, and combining several pulleys makes heavy objects far easier to raise.
Key Words
Tap a word to see its definition.
Materials Needed
- weights
- spring scale
Safety First
- Have an adult check your set-up before you start, and tidy everything away afterwards.
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.
Draw a detailed diagram of what you observe.
Write a conclusion: what did your results show? Did they match your prediction?
Check Your Understanding
Question 1
1 of 3What is work in science?
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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Pulleys Lift Loads
Predict it first. Then prove yourself right (or wrong).
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