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Question
If `vecE` and `vecB` represent electric and magnetic field vectors of the electromagnetic wave, the direction of propagation of the electromagnetic wave is along ______.
Options
`vecE`
`vecB`
`vec(B) × vec(E)`
`vecE × vecB`
Solution
If `vecE` and `vecB` represent electric and magnetic field vectors of the electromagnetic wave, the direction of propagation of the electromagnetic wave is along `underlinebb(vecE × vecB)`.
Explanation:
A changing electric field produces a changing magnetic field and vice versa which gives rise to a transverse wave known as electromagnetic wave. The time-varying electric and magnetic fields are mutually perpendicular to each other and also perpendicular to the direction of propagation of this wave. The electric vector is responsible for the optical effects of an EM wave and is called the light vector.
The direction of propagation of the electromagnetic wave is perpendicular to both electric field vector `vecE` and `vecB` magnetic field vector B, i.e., in the direction of `vecE xx vecB`.
Here, the electromagnetic wave is along the z-direction which is given by the cross product of `vecE` and `vecB`.
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