How Prisms Split Light

A prism is a triangular piece of glass that can split white light into a rainbow of colors. When white light enters the prism, it slows down and bends. Each color of light bends a slightly different amount. This separates the colors so you can see each one individually.

How Light Bends in a Prism

White light is a mixture of all colors. When it enters the prism at an angle, it slows down and bends. This bending is called refraction. Red light bends the least and violet light bends the most. As the light exits the other side of the prism, it bends again. The colors spread out into a band called a spectrum.

Newton's Discovery

Isaac Newton performed a famous experiment with prisms in 1666. He used a prism to split sunlight into a rainbow. Then he used a second prism to combine the colors back into white light. This proved that white light is a mixture of all colors, not a single color. It was a groundbreaking discovery.

Fun Facts

• A diamond acts like a prism, splitting light into sparkles of color called fire.
• Rainbows form because raindrops act like tiny prisms in the sky.
• Newton identified seven colors in the spectrum: red, orange, yellow, green, blue, indigo, and violet.

Did You Know?

The album cover of Pink Floyd's famous album The Dark Side of the Moon shows a prism splitting white light into a rainbow. It is one of the most recognized album covers in music history and was inspired by Newton's light experiments!