The Electromagnetic Spectrum

1. The Electromagnetic Spectrum A continuous range of oscillating electric and magnetic waves. • The energy in an electromagnetic wave increases as the frequency is increased • following E=hf, where h=6.63x10-34 Js (Planck’s constant). • As the frequency of an electromagnetic wave increases, the wavelength decreases • And visa-versa. • All components of the electromagnetic spectrum travel at 3.00 x108 m/s in a vacuum.

2. Power Waves • Electromagnetic waves of frequency 60 Hz resulting from alternating current. • Frequency: 60 Hz • Wavelength: 5x106 m

3. Radio Waves • Electromagnetic waves that oscillate between .53-890x106 Hz. • Wavelength: 570-.34 m • AM: .53x106 Hz to 1.7x106 Hz (570m to 186 m) • FM: 88x106 Hz to 108x106 Hz (3.4 m to 2.8m) • TV: 54X106 Hz to 890x106 Hz (5.6 m to .34 m)

4. Microwaves • Electromagnetic waves that oscillate from 109 to 1011 Hz that has a corresponding wavelength of 10-1m to 10-3m. • Used are in radar, communication and food applications.

5. Infrared Radiation • 1011 to 1014 Hz (10-3 to 10-7 m) • The frequency range that heat is emitted.

6. Visible Light • The range of electromagnetic energy that stimulates the retina of the eye. • 4.0-7.0x1014 Hz (7x10-7 m to 4x10-7 m or 700 nm to 400 nm) • ROYGBIV • Red, Orange, Yellow, Green, Blue, Indigo, Violet. • The frequency of light increases from red to violet. • The wavelength of light decreases from red to violet. • Each wavelength is approximately 50 nm long.

7. Ultraviolet Radiation • 1014 to 1017 Hz (10-7 to 10-10 m) • The portion of the electromagnetic spectrum responsible for sunburn • Ozone absorbs ultraviolet rays. • Most ultraviolet rays are absorbed by glass.

8. X-rays • 1017 to 1019 Hz (10-10 to 10-12 m) • X-Rays are absorbed by denser materials.

9. Gamma Rays • Above 1019 Hz (below 10-12 m) • Produced in nuclear reactions and certain types of radioactive activity. See pages 644-649