what happens when a coil is continuously rotated in uniform magnetic field and does it helps to generate electric current
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When a coil is continuously rotated in uniform magnetic field with its axis perpendicular to the magnetic field, the magnetic field line passing through the coil change and included current is set up in it.
It works on the principle of ' electromagnetic induction'.
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It works on the principle of ' electromagnetic induction'.
HOPE IT WILL HELP YOU !!!!
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refer to Faraday’s law, which arises from the Maxwell equations of electromagnetism. That’s the simplest calculation method, but an intuition for “why” it happens may be easier from the local point of view of an individual conduction charge (usually an electron). To summarize, think of a plane perpendicular to the magnetic field: electrons moving with a rotating conducting loop through the region in front of the plane are magnetically forced upward, and on the other side of the plane have opposite rotational velocity and so are forced downward, generating a circulating current in the conductor.
To see this, remember that any charge qq moving with velocity vv in a magnetic field BBexperiences a “Lorentz” force F=qv×B/cF=qv×B/cperpendicular to both vv and BB. I still remember the geometry/signs with sophomoric humor: hold your right thumb, index finger, and middle finger at right angles to each other and think “FBI”’ with the middle finger rudely being FF, and thumb then being I=qvI=qv. The rotation of a conducting loop carrying electrons along with/inside the wire gives each electron a velocity perpendicular to the wire, and so gives a Lorentz force with a component along the wire, pointing up along the half of the loop with positive transverse velocity, and of course down along the other half of the loop (with negative transverse velocity since it’s turning in a circle). Since the force is always “up” in the region in front of the plane perpendicular to the magnetic field, and “down” in the opposite region, then as the wire rotates across the plane, the force in any one location in the wire reverses sign twice per rotation, so it generates AC at the rotation frequency, instead of DC.
There are no complications from the generated current adding a component of electron velocity along the wire: that just results in a Lorentz force across the wire which builds up an almost unnoticeable charge gradient across the wire (Hall effect), whose small electric field across the wire then cancels Lorentz force across it but has no effect on generated current along it.
To see this, remember that any charge qq moving with velocity vv in a magnetic field BBexperiences a “Lorentz” force F=qv×B/cF=qv×B/cperpendicular to both vv and BB. I still remember the geometry/signs with sophomoric humor: hold your right thumb, index finger, and middle finger at right angles to each other and think “FBI”’ with the middle finger rudely being FF, and thumb then being I=qvI=qv. The rotation of a conducting loop carrying electrons along with/inside the wire gives each electron a velocity perpendicular to the wire, and so gives a Lorentz force with a component along the wire, pointing up along the half of the loop with positive transverse velocity, and of course down along the other half of the loop (with negative transverse velocity since it’s turning in a circle). Since the force is always “up” in the region in front of the plane perpendicular to the magnetic field, and “down” in the opposite region, then as the wire rotates across the plane, the force in any one location in the wire reverses sign twice per rotation, so it generates AC at the rotation frequency, instead of DC.
There are no complications from the generated current adding a component of electron velocity along the wire: that just results in a Lorentz force across the wire which builds up an almost unnoticeable charge gradient across the wire (Hall effect), whose small electric field across the wire then cancels Lorentz force across it but has no effect on generated current along it.
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