Q. The instantaneous magnitudes of the electric field $(E)$ and the magnetic field $(B)$ vectors in an electromagnetic wave propagations in vacuum are related as

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A

$E=\frac{B}{C}$

B

$E=C B$

C

$E=\frac{B}{c^{2}}$

D

$E=c^{2} B$

Solution:

At every instant the ratio of the magnitude of the electric field to that of magnetic field in an electromagnetic wave equal to the speed of light.

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