# What is the change in magnetic flux through the coil?

## What is the change in magnetic flux through the coil?

There are three ways to change the magnetic flux through a loop: Change the magnetic field strength (increase, decrease) over the surface area. Change the area of the loop (increase by expanding the loop, decrease by shrinking the loop) Remember that flux is the integral of the dot product between B and dA.

### What causes a change in magnetic flux?

The change could be produced by changing the magnetic field strength, moving a magnet toward or away from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.

What is the phenomenon of electromagnetic induction?

Electromagnetic induction is a phenomenon in which a changing magnetic field across a loop of wire results in an induced emf. When there is relative motion between a magnet and the coil, magnetic flux changes and hence an electromotive force is generated in the coil.

What is induced due to the change in number of magnetic field lines?

The change in magnetic field lines in a coil is the cause of induced electric current in it.

## What is the change in magnetic flux?

Any change in magnetic flux induces an electromotive force (EMF) opposing that change—a process known as induction. Motion is one of the major causes of induction.

### How does change in magnetic flux induced current?

If a coil of wire is placed in a changing magnetic field, a current will be induced in the wire. A changing magnetic field through a coil of wire therefore must induce an emf in the coil which in turn causes current to flow.

Which things are changed in the phenomenon of electromagnetic induction?

Electric generators use electromagnetic induction to change kinetic energy to electrical energy.

Does change in magnetic flux induced emf or current?

Does change in magnetic flux induce emf or current? Whenever the circuit is closed, there will be an induced current produced linked with change of magnetic flux in the coil. However, change in magnetic flux always induce emf in the circuit whether it is open or close.

## What is a change in flux?

The induced EMF produces a current that opposes the change in flux, because a change in flux means a change in energy. Energy can enter or leave, but not instantaneously. Lenz’ law is a consequence. As the change begins, the law says induction opposes and, thus, slows the change.

### What happens when the magnetic flux through a wire changes?

If the magnetic flux through a loop of wire changes for any reason either by changing the area, A, of the loop or the field, B, through the loop Then an EMF (voltage) will be induced in the wire. This voltage will cause a current to flow (the induced current in the loop).

What causes a change in the magnetic field?

The change could be produced by changing the magnetic field strength, moving a magnet toward or away from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.

When does a moving magnet produce an induced current?

Figure 23–2 Induced current produced by a moving magnet A coil experiences an induced current when the magnetic field passing through it varies. (a) When the magnet moves toward the coil the current is in one direction. (b) No current is induced while the magnet is held still.

## What happens when a magnet is pulled away from a coil?

(c) When the magnet is pulled away from the coil the current is in the other direction. Also, changing the shape of a loop in or relative to a magnetic field would cause a blip on an ammeter. Change in the number of field lines through a coil gives a current. Number of field lines through a coil is called magnetic flux