Summary
Why do anchors sink while boats float? In this BrainPOP movie, Tim and Moby dive into buoyancy, the special property of fluids that acts against gravity. See how much water is displaced when an unsuspecting robot is dropped into a pool. Learn how the buoyant force makes objects weigh less underwater. And discover how an object's density determines whether it sinks, floats, or hovers in a fluid. With all this knowledge, you'll surely be able to keep your head above water!
Viewer safety
Ages 7+
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Teaching resources
Discussion questions
A few questions to talk through after watching Buoyancy:
- What is one new thing you learned about buoyancy?
- Can you explain it to a partner in your own words?
- Where might you see this in the real world?
- What is one question you still have?
Quick work-a-long
Try it:
- Write one sentence explaining buoyancy.
- Draw or give one example of your own.