3 Electromagnetic Spectrum
Electromagnetic Spectrum
DIFFERENT TYPES OF ELECTROMAGNETIC WAVES | |||
Type | Wavelength range | Production | Detection |
Radio | > 0.1 m | Rapid acceleration and decelerations of electrons in aerials | Receiver’s aerials |
Microwave | 0.1Â m to 1 mm | Klystron valve or magnetron valve | Point contact diodes |
Infra-red | 1Â mm to 700 nm | Vibration of atoms and molecules | Thermopiles, bolometer, infrared photographic film |
Light | 700 nm to 400 nm | Electrons in atoms emit light when they move from one energy level to a lower energy level. | The eye, photocells, photographic film |
Ultraviolet | 400 nm to 1nm | Inner shell electrons in atoms moving from one energy level to a lower level | Photocells, photographic film |
X-rays | 1 nm to 10−3nm | X-ray tubes or inner shell electrons | Photographic film, Geiger tubes, ionisation chamber |
Gamma rays | <10−3 nm | Radioactive decay of the nucleus | -do- |
Different Types of Electromagnetic Waves