Electromagnetic Spectrum

The electromagnetic spectrum covers a wide

range of wavelengths and photon energies.

Two types of wavesTransverse (no medium required)

andCompression (must have a medium)

Wavelength:the distance between two identical points on two adjacent

waves

Frequency is the number of wave crests that pass a point

during one second.

These waves go from Large to smallRadio

MicrowavesInfrared

Visible LightUltraviolet

X-RaysGamma Radiation

Electromagnetic waves are produced by the motion of electrically charged particles

Particle Wave Duality: Electomagnetic radiation acts as a wave but also as a particles (“Photons” which is a stream of particles that has no mass.)

Visible Light

Why is the sky blue?

Why is the sky blue?Rayleigh Scattering

Rayleigh Scattering: light hits gas molecules and the different

frequencies are all effected differently.Higher frequencies (blue) are

absorbed much more often then lower frequencies (red)

The gas will eventually radiate the blue light back out scattering it out

making the sky appear blue.

Why do you get different colors at

sunset or when there are more clouds in the

sky?

Ticket out the door1. What is the largest wavelength

we know about?2. Are light wave transverse or

compression waves?3. Why is the sky blue?