Rocket squeezes a big spring from an old toy.
"It is fighting me!" he says. His hand shakes.
Raven asks, "What do you notice when you squeeze harder?"
Nova hums. "Would you like a hint? Think about pushes and pulls."
A push or a pull is called a force.
When you squeeze a spring, you push on it.
The spring pushes back on your hand.
When you stretch a spring, you pull on it.
The spring pulls back on your hand.
Squeeze a spring a little. It pushes back a little.
Squeeze it a lot. It pushes back a lot.
The spring always pushes toward its own shape.
That is why the spring stores a push.
A spring can make something move, like a wind-up toy.
A spring can also make something stop, like a door stop.
A pogo stick uses a squeezed spring to bounce.
A jack-in-the-box uses a squeezed spring to pop up.
| Thing | Squeezed or stretched? | What the spring does |
|---|---|---|
| Pogo stick | Squeezed | Bounces you up |
| Jack-in-the-box | Squeezed | Pops the toy up |
| Click pen | Squeezed | Pushes the tip back |
| Door stop | Squeezed | Stops the door |
| Sentence | True or false? |
|---|---|
| A push or a pull is a force. | ? |
| A squeezed spring pushes back. | ? |
| A tiny squeeze pushes back more than a big squeeze. | ? |
| A spring can make a toy move. | ? |
You felt a spring push back. Super science!
Tomorrow, we take apart an old click pen.