What is the em spectrum
A family of waves with similar properties. They’re organised by their frequency and wavelength.
What’s the same for all waves
• all transverse waves
• travel at the speed of light
(3x10^8 m/s)
What’s different about the waves
Frequency, wavelength, energy
What is ionisation of cells
Electrons can be removed from atoms when uv, x, gamma rays are absorbed. This leads to mutations and possibly cancers.
Why do some waves cause ionisation but others do not
Higher frequency regions have more energy so can ‘move’ electrons.
Higher frequency regions have smaller wavelengths so interact with matter at an atomic scale.
How does frequency vary
Long wavelength= lower Frequency
Frequency is the same as Energy
How energy varies
Higher Energy = Short wavelength
Energy=Same as Frequency
How Wavelength varies
High frequency = Short wavelength
Lower Frequency = Longer wavelength
What are em waves (transverse)
Transverse waves which transfer energy from the source of the waves to an absorber.
What happens when we heat atoms
Electrons gain energy -> release it as EM waves
