the electromagnetic spectrum. what is light? light is a form of radiant energy that you can see. the...
TRANSCRIPT
The Electromagnetic Spectrum
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.
• Electromagnetic Spectrum:
• http://www.brainpop.com/science/energy/electromagneticspectrum/preview.weml
• Energy can be transmitted as a wave. Light travels as a wave.
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.
The Wave
• One wavelength is the distance from crest to crest or from tough to trough.
Definitions…
• Amplitude: The crest height (or depth of the trough) from the equilibrium position.
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.
Colours and their Wavelengths
• Red – 700 nm• Orange – 600 nm• Yellow – 580 nm• Green – 510 nm• Blue – 475 nm• Violet – 400 nm
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.
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.