Home » Posts tagged 'magnetic fields'
Tag Archives: magnetic fields
We know that photon has no charge. Then where from it gets electric and magnetic field in light?
Malik Sajad asks
Electric and magnetic fields are not produced by the photon; it is massless too.
But, photon is created by time varying electric and magnetic fields, usually produced by accelerated charges.
As you might have already learnt, a charge at rest produces an electric field around it. A moving charge (current) produces a magnetic field around it as well as magnetic field. A varying current produces a varying magnetic field and hence an induce emf or current. An accelerated charge produces a time varying electric and magnetic fields.
Thus under suitable situations, the electric and magnetic fields can reinforce each other and propagate out as pure electromagnetic form of energy and such a packet of energy is called photon.
What is resultant magnetic force? can you please explain with an example.
When a magnetic substance (or a magnet) is placed in a region where there are multiple magnetic fields, the net force due to all of them is called the resultant.
In other words, it is that magnetic force which can effectively replace all other magnetic force acting on it
(Need more explanation? Post as comment to this post for details)