1. How do waves interact?

2. Reflection Reflection: Happens when a wave bounces back after hitting a barrier. Reflection: Happens when a wave bounces back after hitting a barrier. How we see light! The object reflects light of the color seen How we see light! The object reflects light of the color seen Sound, light, and water waves can all be reflected: Sound, light, and water waves can all be reflected: Sound: Echo Sound: Echo Light: How we see the planets and Moon. The planets reflect the light of the sun. Light: How we see the planets and Moon. The planets reflect the light of the sun.

3. Absorption and Scattering Absorption: The transfer of light energy of particles of matter. Absorption: The transfer of light energy of particles of matter. Scattering: An interaction of light with matter that causes light to change its energy, direction of motion, or both Scattering: An interaction of light with matter that causes light to change its energy, direction of motion, or both Picture on 646 Picture on 646

4. Refraction Refraction: The bending of a wave as the wave passes between two substances in which the speed of the wave differs. Refraction: The bending of a wave as the wave passes between two substances in which the speed of the wave differs. Moves from one medium to another. The wave speed changes, therefore the wavelength changes. Moves from one medium to another. The wave speed changes, therefore the wavelength changes. Rainbows: Occur because sunlight is refracted through water droplets. The colors occur because the different colors in sunlight is refracted by different amounts, and spread out into different colors. Rainbows: Occur because sunlight is refracted through water droplets. The colors occur because the different colors in sunlight is refracted by different amounts, and spread out into different colors.

5. Diffraction Diffraction: A change in the direction of a wave when the waves finds an obstacle, edge, such as an opening. Diffraction: A change in the direction of a wave when the waves finds an obstacle, edge, such as an opening. Light: Long wavelengths, don’t diffract very much. Light: Long wavelengths, don’t diffract very much. Sound: Shot wavelengths, easily diffracted. Sound: Shot wavelengths, easily diffracted.

6. Interference Interference: The result of two or more waves overlapping. Interference: The result of two or more waves overlapping. Constructive: When the crest or troughs of two waves overlap and creates a bigger wave, with a larger amplitude. Constructive: When the crest or troughs of two waves overlap and creates a bigger wave, with a larger amplitude. Destructive: Crest of one wave and the trough of another wave overlap. This results in no wave at all. Destructive: Crest of one wave and the trough of another wave overlap. This results in no wave at all.