The intensity of an electromagnetic wave is 20 W/m^2?
What will the intensity be if: the amplitude of the electric field is doubled?
What will the intensity be if: the amplitude of the magnetic field is doubled?
What will the intensity be if: the amplitudes of both the electric and the magnetic field are doubled?
What will the intensity be if: the frequency is doubled
4 Answers
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The EM wave intensity is given by:
S = ½ cεo Eo² = (1/µo) EoHo, W/m²
If electric field amplitude, Eo, is doubled; then S is quadrupled.
If magnetic field amplitude, Ho, is doubled; then S is quadrupled.
If both fields are doubled; then S is quadrupled.
If frequency is doubled; S is unchanged.
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Electromagnetic Wave Intensity
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Intensity Of Electromagnetic Wave
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If the electric field is doubled the intensity will be 80 W/m^2
Likewise if the magnetic field is doubled the intensity will be 80 W/m^2
If either the electric field is doubled the magnetic field is also doubled, likewise if the magnetic field is doubled the electric field is doubled
Frequency has nothing to do with the intensity of an electromagnetic field.
