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Have a look at the image below, enter image description here

It depicts Electric and Magnetic field components of electromagnetic wave.

I'm a bit confused about whats happening here.I mean is the electric field changing with time or position and what do the waves actually represent(the intensity or direction)...

Divyanshu
  • 478

2 Answers2

1

See the animation below. A light ray is travelling along the $x$-axis, the arrows are the vectors for $E$-field (orange) and $B$-field (cyan) at the corresponding position $\mathbf{r}=(x,0,0)$. The wave function can be written as follows:

$$\mathbf{E}(x,0,0,t)= E_0 \sin \left( \dfrac{ct-x}{\lambda} \right) \, \mathbf{e}_{y}$$

$$\mathbf{B}(x,0,0,t)= B_0 \sin \left( \dfrac{ct-x}{\lambda} \right) \, \mathbf{e}_{z}$$

where $E_0=cB_0$ or precisely $\mathbf{k}\times \mathbf{E}=\omega \mathbf{B}$.

enter image description here

Ng Chung Tak
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0

The picture gives you a snapshot in time of both the directions and field strengths of a plane electromagnetic wave propagating in x-direction. The arrow indicates the propagation direction of this wave with time, which would give you a shift of the field strength patterns in positive x-direction by $\Delta x=c\Delta t$ where $\Delta t$ is the elapsed time after the time of the snapshot.

freecharly
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