The Electromagnetic Spectrum
- The electromagnetic spectrum is a range of frequencies that includes all wavelengths of electromagnetic radiation
- The spectrum connects three important variables in the study of light: frequency, wavelength and energy
- Wavelength is the distance between two consecutive crests on a wave
- Frequency is how many waves occur per second
- The higher energy radiations correspond to the shorter wavelengths
- High energy and high frequency radiation is very damaging for living beings
The electromagnetic spectrum diagram
The electromagnetic spectrum spans a broad spectrum from very long radio waves to very short gamma rays
- All the light waves travel at the same speed, the only thing that is different is their frequencies
- The speed of light (c) is a constant and it has a value of 998 x 108 ms-1
- Molecules behave in particular ways when they are exposed to radiation of different frequencies
- When exposed to microwaves, molecules will rotate
- When exposed to infrared radiation, molecules will vibrate
- When exposed to ultraviolet or visible radiation, the electrons will jump between energy shells