Lesson 55 of 84 · Energy
Lesson⭐ 30 XP⚡ Spark LabPulleys Lift Loads (Part 2)
Pulleys Lift Loads (Part 2).
🎯 Your mission
Master the concept. Use it tomorrow.
⚡ 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.
Steps
Review the background information on Energy before starting.
Test Newton's Third Law: blow up a balloon, attach it to a straw on a string, and release. Measure how far it travels with different amounts of air.
Use your senses (except taste) to describe what you notice.
Write a summary of your findings in 3-5 sentences.
Check Your Understanding
Question 1
1 of 3What is the formula for Newton's second law?
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.”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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