Delilah is quite happy—
She loves a rainy day.
She grabs her boots and raincoat
And runs right out to play.
The rain is not a problem
Because her coat’s so slick.
She never comes home soaking
The water drops don’t stick.
Drops slide right off her raincoat,
As if they’re in a race.
That’s why it is a raincoat—
Drops leave without a trace!
What You’ll Need
- piece of cardboard
- sheet of white paper
- wax paper
- water
- watch with a second hand
- tape
Why don’t water drops stick to Delilah’s
raincoat or racetrack?
The tiny particles that make up water are strongly attracted to each other. They stick together to form drops, but the plastic in a raincoat and the wax in the wax-paper racetrack are made from substances with oil in them. Water and oil are not attracted to each other, so the drops roll right off.