Light acts like both a particle and a wave, but never both at the same time. But you need both of these concepts in order to fully describe how light works.

Energy can take one of two forms: matter and light (called electromagnetic radiation). Light is energy in the form of either a particle (like a marble) or a wave that can travel through space and some kinds of matter (like a wave on the ocean). You really can’t separate the two because they actually complement each other.

Low electromagnetic radiation (called radio waves) can have wavelengths longer than a football field, while high energy (gamma rays) can destroy living tissue. Light has wavelength (color), intensity (brightness), polarization (the direction of the waves that make up the light), and phase.

Materials: sink or bowl of water, glow in the dark toy, camera flash or sunlight

4 Responses to “Wave-Particle Duality of Light”

1. Yes you can use a flashlight or even sunlight to charge up the phosphorescent particles, but it will take longer than the higher energy camera flash burst.

2. Julia Raudenbush says:

Could a flashlight be used instead of a camera light or is it the quick burst of light that you’re going for?

3. You’re right, the speed is the same for all electromagnetic radiation. The differences remain the frequency, wavelength, and energy of the radiation, and thus we get the attending differences in color. A prism refracts and breaks up the light, which means that the light changes direction and is broken into slightly different wavelengths, which we observe as changes in color.

4. Hyder Khan says:

One question jost popped in my mind when you said that when white light passes through a prism, different colors or different wavelengths travel at different speed so the white light is broken out in different colors.

My understanding about electromagnetic waves is, this that they all (from radio-waves to gamma-waves) travel at the same speed in any medium.
Could it be that, waves of different wavelengths are bend to different degree as they pass through prism and so they are separated and a rainbow is formed? Their speed remains the same.