1. They all travel as electromagnetic waves!
What is the link?
They all travel as electromagnetic waves!

2. The electromagnetic spectrum
02/12/2018
The electromagnetic spectrum
Objectives:
Be able to…
Recall the order of the EM spectrum
Describe the properties of waves in the EM spectrum
Calculate the speed of waves

3. Waves Amplitude = the height or depth of the wave from the middle
Wavelength = distance from one wave crest to the next crest
Amplitude = the height or depth of the wave from the middle
Frequency = the number of wave crests per second

4. Electromagnetic waves
They do not transfer matter –
they transfer energy
The energy they transfer depends on the wavelength of the waves

5. The electromagnetic spectrum
Radio
Micro-wave
Infra-red
Visible light
Ultra-violet
X-ray
Gamma ray
Long Wavelength
Short Wavelength
Low Frequency
High Frequency

6. Properties of EM waves
EM waves are transverse (sound waves are longitudinal)
EM waves can travel through a vacuum (this is how the Sun’s heat and light reach Earth)
All waves travel at the same speed in a vacuum (300,000,000 m/s – the speed of light)

7. Waves with short wavelengths carry more energy
Properties of EM waves
Waves with short wavelengths carry more energy

8. This is the Greek letter lambda – it stands for wavelength!
Speed of EM waves
wave speed = frequency × wavelength
v = f x l
(m/s) (Hz) (m)
This is the Greek letter lambda – it stands for wavelength!

9. Speed of EM waves v
wave speed (m/s) f l
frequency (Hz)
wavelength (m)

10. Speed of EM waves Example:
A mobile phone gives out EM waves of frequency 900 million Hz. Calculate the wavelength of these waves. Speed of EM waves in air = 300 million m/s.
Wavelength = speed
frequency
l =
l = 0.33m

11. Radio Microwaves Infrared Visible light Ultraviolet X rays Gamma
Create a mnemonic to remember the order of the EM spectrum
Radio Microwaves Infrared Visible light Ultraviolet X rays Gamma