Find Magnetic Field Amplitude from EM Wave Amplitude

tquiva
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Homework Statement



A plane electromagnetic wave propagating in free space has an amplitude (\sqrt{3}/2)a_{y}-(1/2)a_{z} V/m. Find the amplitude of the accompanying magnetic field assuiming the frequency of the electric field is 1 GHz.

Homework Equations



f_{E} = f_{H}

\frac{E_{0}}{B_{0}} = \frac{ω}{k} = c

The Attempt at a Solution



I know that the frequency for both the Electric and Magnetic fields are equivalent. Therefore, the magnetic field frequency is also 1 GHz.

However, the question says "electromagnetic wave." This term means the cross product result or E x B right? With that being said, I'm not sure how to obtain the amplitude of the magnetic field if I don't have any info for the electric field.

Or is there some other equation related to the EM wave?

Any help or suggestions is greatly appreciated!
 
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tquiva said:
..., the question says "electromagnetic wave." This term means the cross product result or E x B right? With that being said, I'm not sure how to obtain the amplitude of the magnetic field if I don't have any info for the electric field.
But you are provided with "info for the electric field": the frequency and the amplitude. What else do you need?

For EM radiation the E and B components have a special relationship.
 
tquiva said:

Homework Statement



A plane electromagnetic wave propagating in free space has an amplitude (\sqrt{3}/2)a_{y}-(1/2)a_{z} V/m.

Perhaps it was meant the vector amplitude of the electric field.

ehild
 

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