Electromagnetic Spectrum in a Nutshell
Electromagnetic spectrum is the range of wavelengths or frequencies over which
electromagnetic radiation extends. This spectrum includes:
1. Gamma Ray
λ= 1.0 X 10-11 m
Source: Radioactive matter
2. X-Ray
λ= 1.0 X 10-9 m
Source: X-ray tube
Produced due to the rapid deceleration of electrons by a metal target
in an X-ray tube
3. Ultraviolet Radiation (UV)
λ= 1.0 X 10-7 m
Source: Mercury lamp
4. Visible Light (red, orange, yellow, green, blue, indigo, violet)
λViolet= 4.0 X 10-7 m
λRed= 7.0 X 10-7 m
Source: Sun
5. Infrared Radiation
λ= 1.0 X 10-5 m
Source: Electric fire
Below 500°C => hot, not glowing: emits only IR Increasing Decreasing
wavelength wavelength
At about 500°C => red hot, glowing: emits IR and red light
& &
At about 1500°C => white hot: emits IR and white light Decreasing Increasing
frequency frequency
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Electromagnetic spectrum is the range of wavelengths or frequencies over which
electromagnetic radiation extends. This spectrum includes:
1. Gamma Ray
λ= 1.0 X 10-11 m
Source: Radioactive matter
2. X-Ray
λ= 1.0 X 10-9 m
Source: X-ray tube
Produced due to the rapid deceleration of electrons by a metal target
in an X-ray tube
3. Ultraviolet Radiation (UV)
λ= 1.0 X 10-7 m
Source: Mercury lamp
4. Visible Light (red, orange, yellow, green, blue, indigo, violet)
λViolet= 4.0 X 10-7 m
λRed= 7.0 X 10-7 m
Source: Sun
5. Infrared Radiation
λ= 1.0 X 10-5 m
Source: Electric fire
Below 500°C => hot, not glowing: emits only IR Increasing Decreasing
wavelength wavelength
At about 500°C => red hot, glowing: emits IR and red light
& &
At about 1500°C => white hot: emits IR and white light Decreasing Increasing
frequency frequency
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