Why Does Crinkled Foil Sparkle in Every Direction?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why does crinkled foil sparkle in every direction?

The Big Idea

Smooth foil acts like a mirror, sending light in one direction. Crinkled foil has lots of tiny flat patches, all pointing in different directions. Each one flashes light somewhere else, so you see sparkle in every direction.

Smooth Foil

Step one: smooth foil. Flat foil reflects light in one direction, just like a mirror does. From the right angle, you see a clear, bright picture.

Crinkled Foil

Step two: crinkled foil. Crumpling makes lots of tiny flat patches, like a landscape of little hills and facets. Each patch tilts a different way, so they all point at different spots.

Sparkle Everywhere

Step three: sparkle everywhere. Each patch sends light off in its own direction. So some patch is always flashing toward your eyes, wherever you stand.

A Closer Look

Let's take a closer look! Smooth one half of a piece of foil with your hand. Crinkle the other half into little wrinkles. The smooth half shows a clear reflection. The crinkled half sparkles in every direction.

Quick Facts

Quick facts! Disco balls and glitter seem to sparkle everywhere for the same reason. A disco ball is covered in little flat mirrors. Foil is aluminum metal rolled out super thin, much thinner than paper. Be careful of the foil's sharp edges.

Think Like a Scientist

Now, think like a scientist! Smooth one half of a piece of foil, and wrinkle the other half. Hold it under a lamp. Which half shows a clear reflection? Which half sparkles? Be careful of the sharp edges.

Outro

Crinkled foil sparkles because its tiny patches face every way. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!