Density
What is Density
Density is how heavy something is for its size.
Imagine you have a big sponge and a small rock.
The sponge is bigger, but it’s very light.
The rock is smaller, but it feels heavy.
That’s because the rock is more dense — all its stuff is packed tightly inside.
The sponge is less dense — it has more air and is lighter for its size.
So, density is like asking:
“How much stuff is packed inside something?”
So, density is like asking:
“How much stuff is packed inside something?”
Activity: Sink or Float? (A Fun Way to See Density)
🧻 What You Need:
A plastic bottle cap
A clear bowl or cup of water
A small rock
A sponge
A crayon
A piece of apple
A coin
What To Do:
- Fill the bowl with water.
- One by one, gently drop each object into the water.
- Watch: Does it sink or float?
- Sort them into two groups:
- Floaters (less dense than water)
- Sinkers (more dense than water)
🧠 What’s Happening?
- If something floats, it’s less dense than water.
- If something sinks, it’s more dense than water.
Explain Like This:
“Even though the sponge is big, it floats because it’s full of air.
The little coin sinks because it’s small but very heavy for its size. That means it’s denser!”
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