We zoom into an atom, meet Scientist Bob, and figure out why a helium balloon floats to the ceiling while a regular one just sits there. Atoms, molecules, and physics — explained.
Atoms are so tiny that millions of them could fit on the tip of a pencil.
Electrons zoom around the nucleus of an atom kind of like planets orbiting the sun.
Air counts as a fluid too — it's made of gas molecules that flow and push, just like water.
Helium floats up because it's less dense than the air around it — lighter stuff gets pushed to the top.
Density decides who wins — whatever has more mass packed into the same space gets pulled down harder by gravity, and sinks below the rest. Tap something below and see what happens.
Helium is less dense than air, so gravity pulls harder on the air around it — up it goes!
Remember Scientist Bob from the episode? Ask him anything about atoms, molecules, fluids, or why balloons float.
Ask away — I once fell through a dimension to show you an atom.
Scientist Bob is an AI and can make mistakes — always double check with a grown-up.
Snap a photo of any food and Pear AI whips up a recipe with nutrition facts. Get it free at kidslearninglab.com/pear.