1. Light and the Atomic Spectra
Chapter 13-3

2. Electromagnetic radiation Light consists of electromagnetic waves.
A form of energy
Includes:
Radio waves
Microwaves
Infrared waves
Visible light
Ultraviolet light
X-rays
Gamma rays

3. The electromagnetic spectrum

4. Electromagnetic waves
All electromagnetic waves travel in a vacuum at a speed of 3.0 x 108 m/s.

5. How to calculate the frequency and wavelength.
Their frequency and wavelength can be determine by the following formulas.
Frequency = c / λ
λ= c/frequency
where 'c' is the speed of light in meters per second, the Greek letter lambda λ is the wavelength in meters and the frequency is in cycles per second also known as Hertz.

6. Common symbols and units
Name
Symbol
Units
Frequency
ν or f
S-1 or Hz
Wavelength λ m
Electromagnetic speed c
m/s

7. Amplitude
Wavelength
(λ)
Frequency
(ν)
Amplitude of the wave is the wave’s height from the origin to the crest.
Is the distance between the crests.
It is the number of wave cycles to pass a given point per unit of time.

8. Anatomy of the wave

10. How to calculate the energy
the photon energy can be calculated by the formulas:
e = h ∙ f
h ∙ c
e = λ