 Electromagnetic waves are transverse waves that do not need a medium to travel › This means they can travel in space!  The transfer of energy by electromagnetic waves is called radiation

 Electromagnetic waves have a wide range of wavelengths, frequencies and energy  The arrangement of electromagnetic waves according to their wavelengths is called the Electromagnetic Spectrum

 Speed = wavelength x frequency  (as 1 the other )  Waves with the longest wavelength have the lowest frequencies and the lowest energy  Waves with the shortest wavelengths have the highest frequencies and the highest energy

 Longest wavelength  Lowest frequency  Lowest energy  Examples: › Radio < FM / AM › TV › Radar

 2 nd longest wavelength  2 nd lowest frequency and energy  Examples: › Cell phones › Microwave Ovens

 The energy you feel as heat (heat rays)  3 rd longest wavelength  3 rd lowest frequency and energy  Examples: › Heat lamps › TV remotes

 The only EM wave we can see!  Middle of the spectrum  ROY G B(I)V < longest wavelength to shortest wavelength

 3 rd shortest wavelengths  3 rd highest frequency and energy  Examples:  Sun burn  Black lights  Sterilizers

 2 nd shortest wavelength  2 nd highest frequency and energy  Pass through skin and soft tissue but not bone or lead

 Shortest wavelength  Highest frequency  Highest energy  The most penetrating and dangerous waves of the EM spectrum  Examples: › Certain nuclear reactions › Kill cancer cells › Examine body’s internal organs