Lesson 4 of 6 · Energy
Experiment⭐ 30 XP⚡ Spark LabBuoyancy and Floating
Buoyancy and Floating.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Speed isn't the same as force. Don't mix them up.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Guess: where does the energy go?
What You'll Learn
Buoyancy is the upward force a fluid pushes on an object placed in it. An object floats when the buoyant force pushing up equals the weight pulling down, which is why a heavy steel ship can float while a small pebble sinks.
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 gravity?
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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Buoyancy and Floating
Set it up. Test it. Be amazed.
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