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Hello everybody.
I've been having difficulty in understanding how an electromagnetic wave propagates through space.
Firstly, from what I understand, electromagnetic waves are made up of a constantly varying electric field placed perpendicular and in phase with a constantly varying magnetic field. Now let's set up a source to generate an electromagnetic wave. From the above, the source should consist of a varying electric field and varying magnetic field.
Now consider a point P a distance d away from the source. The time taken for the energy from the wave to reach the point P from the moment the source is switched on would then be
t = d/c.
Isn't the effect of a magnetic or electric field assumed to be instant before relativity showed that information cannot be transferred faster than the speed of light?
Even so, how does 2 perpendicular fields explain how energy is transferred through space? From what I've read from texts its because the electric field induces a magnetic field (Maxwell's law of induction), and the induced magnetic field induces yet another electric field (Faraday's law of induction) and so and so forth. But I failed to understand that as it still does not seem to explain how the wave propagates through space. The induced B-fields and E-fields are still induced in the space about the source, and I'm unable to see how it travels.
Perhaps someone could point me in the right direction?
I've been having difficulty in understanding how an electromagnetic wave propagates through space.
Firstly, from what I understand, electromagnetic waves are made up of a constantly varying electric field placed perpendicular and in phase with a constantly varying magnetic field. Now let's set up a source to generate an electromagnetic wave. From the above, the source should consist of a varying electric field and varying magnetic field.
Now consider a point P a distance d away from the source. The time taken for the energy from the wave to reach the point P from the moment the source is switched on would then be
t = d/c.
Isn't the effect of a magnetic or electric field assumed to be instant before relativity showed that information cannot be transferred faster than the speed of light?
Even so, how does 2 perpendicular fields explain how energy is transferred through space? From what I've read from texts its because the electric field induces a magnetic field (Maxwell's law of induction), and the induced magnetic field induces yet another electric field (Faraday's law of induction) and so and so forth. But I failed to understand that as it still does not seem to explain how the wave propagates through space. The induced B-fields and E-fields are still induced in the space about the source, and I'm unable to see how it travels.
Perhaps someone could point me in the right direction?