1. The Electromagnetic Spectrum

2. What is Light? Light is a form of radiant energy that you can see.
The visible spectrum is only a small part of the range of radiant energies.
The entire range of radiant energies is called the Electromagnetic Spectrum.

3. Electromagnetic Spectrum:

4. Energy can be transmitted as a wave. Light travels as a wave.

5. Colours and Wavelengths
We see different colours when the waves have different wavelengths.
We measure wavelength in nanometers (nm) and the measurement is represented by the symbol lambda, λ.

6. The Wave
One wavelength is the distance from crest to crest or from tough to trough.

7. Definitions…
Amplitude: The crest height (or depth of the trough) from the equilibrium position.

8. How do Waves Travel? Waves transfer energy.
The parts of the Electromagnetic spectrum have common properties, such as their high speed and ability to travel through a vacuum.
Different properties are related to wavelength, frequency and energy.

9. Colours and their Wavelengths
Red – 700 nm
Orange – 600 nm
Yellow – 580 nm
Green – 510 nm
Blue – 475 nm
Violet – 400 nm

10. Frequency
Frequency: The number of cycles completed in a period of time.
The unit of measurement is Hertz (Hz), which represents cycles/second.
High frequency waves are shorter in wavelength and carry more energy.

11. Create your Own Electromagnetic Spectrum
Using long blank white paper create a drawing of the electromagnetic spectrum.
Include the types of waves (radiowaves, microwaves, etc), their range in wavelengths, the wavelengths, and a wave indicating frequency.