would electromagnetic waves exist if changing magnetic fields could produce electric fields but changing electric fields could not in turn produce magnetic fields?
Would electromagnetic waves exist in this situation...?
No, electromagnetic waves rely on the fact that a changing electric field induces a magnetic field and a changing magnetic field produces an electric field.
This property of electric and magnetic fields allow EM waves to be self-propagating and for this reason they can travel through a vacuum (as opposed to sound waves for instance).
Would electromagnetic waves exist in this situation...?
not gettng ur quest dear.... :( its not clear....anyways....
they can produce magnetic fields as well.....
I don't believe that it is possible for alternating magnetic fields to exist without simultaneous alternating electric fields, and vice versa. They may be out of phase with one another, so that the electric field reaches its peak value 1/4 cycle (90 degrees) after the magnetic field does, but you can't have one without the other.
Changing magnetic fields is how a true generator works. Changing electric fields is how an alternator works.
Just take my word for it ok? The Alternator is more efficent because it produces its own magneitc field...
*sigh* Yes, they exist in this situation. No, I don't know how to describe 6 quarters of electrical theory into one paragraph!
No they could not.
If this were so, propagation would depend on the magnetic field alone.The wave would flatten off very fast as the magnetic field weakens in distance from the source.
But it is a well known fact (Maxwell Equations) that changing magnetic fields produce electric fields and changing electric fields in turn produce magnetic fields. Why do you ask?
I'm not sure that an asymetrical relationship like that is even possible in this universe. But assuming you could do it, the waves would collapse almost instantly.
YES, magnetic waves would exist. you must remember that when a magnetic field cuts across(passes in close proximity) to a wire (conductor), a voltage is created in the conductor (wire). The voltage is said to be traveling in one direction along the wire. Observe the polarity of the wire. As this voltage moves along the wire another small magnetic field is created along the length of the wire with it's origin being the center of the wire. When the original magnetic wave dissipates and is no longer moving across the wire (conductor) all voltages fall to zero. However, as these magnetic fields collapse they actually begin cutting conductors with their fields and inducing a voltage that is said to be in the opposite direction. As these fields try to return to their originating site they crash with their counterparts. This power is lost to a term which is called reactance.
No thats what i think.
mrjeffy is right. Mathematically, the proof is that without the symmtery between the changing electric field producing a magnetic field and vice versa, one can no longer write the source free (no charges or currents present) Maxwell Equations as a system of coupled wave equations, therefore, a propagating wave solution would not exist.
