electromagnetic waves

WavesMs. Shinkle

11/2-5, 2007

Types of Waves

• Mechanical Waves– Sound– Earthquake– Springs

• Electromagnetic– Light– Radio – X-ray

Electromagnetic Radiation

• Examples: Radio, TV, Microwave, X-Rays, Gamma Rays, Light, Ultraviolet, Infrared

• Do NOT need a medium– Can travel through space

• How astronomers observe the universe

How Fast?

• EMR is the fastest stuff around• Speed (“c”) is 3×108 m/s• All EMR travels at the same speed• Each type of EMR has a different

wavelength and frequency

A. Baseline E. Positive amplitudeB. Peak F. Negative amplitudeC. Peak to peak wavelength G. TroughD. Trough to trough wavelength

Wave Basics

Electromagnetic Spectrum

How do you make EMR?

• Just like any other wave, something has to move or vibrate

• Only now, it takes an electric charge (like an electron) that vibrates or moves

Wavicles

• EMR can act like a wave – it reflects, refracts, diffracts, etc.

• EMR can act like a particle (Photons)

• That’s what makes solar panels work. It’s called the Photoelectric Effect.

Visible Light in the EMR Spectrum