Question
State two characteristics of an EM wave.
✓
Answer
i. The electric and magnetic fields, $\vec{E}$ and $\vec{B}$ are always perpendicular to each other and also to the direction of propagation of the EM wave. Thus, the EM waves are transverse waves.
ii. The cross product $(\vec{E} \times \vec{B})$ gives the direction in which the EM wave travels. $(\vec{E} \times \vec{B})$ also gives the energy carried by EM wave.
ii. The cross product $(\vec{E} \times \vec{B})$ gives the direction in which the EM wave travels. $(\vec{E} \times \vec{B})$ also gives the energy carried by EM wave.
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