The ratio of amplitude of magnetic field to the amplitude of electric field of an electromagnetic wave propagating in vacuum is
Show Hint
- Reciprocal of speed of light in vacuum
- The speed of light in vacuum
- Proportional to frequency of the electromagnetic wave
- Inversely proportional to the frequency of the electromagnetic wave
The Correct Option is A
Approach Solution - 1
The relationship between the amplitude of the magnetic field (B0) and the amplitude of the electric field (E0) in an electromagnetic wave propagating in vacuum can be described by the equation:
BE=1c
Where,
- B: Amplitude of the magnetic field
- E: Amplitude of the electric field
- c: Speed of light in vacuum (approximately 3×108m/s)
This shows that the ratio of the amplitude of the magnetic field to the amplitude of the electric field in an electromagnetic wave is the reciprocal of the speed of light.
Therefore, the correct option is: Reciprocal of speed of light in vacuum
Approach Solution -2
- \( E \) is the electric field,
- \( B \) is the magnetic field,
- \( c \) is the speed of light in vacuum.
Thus, the ratio of the amplitude of the magnetic field to the amplitude of the electric field is: \[ \frac{B}{E} = \frac{1}{c} \] Therefore, the correct answer is the reciprocal of the speed of light in vacuum.
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