What happens if the wire is stationary in a magnetic field

An emf is induced in the coil when a bar magnet is pushed in and out of it. Emfs of opposite signs are produced by motion in opposite directions, and the emfs are also reversed by reversing poles. The same results are produced if the coil is moved rather than the magnet—it is the relative motion that is important.

The faster the motion, the greater the emf, and there is no emf when the magnet is stationary relative to the coil. Figure 2. Movement of a magnet relative to a coil produces emfs as shown. The same emfs are produced if the coil is moved relative to the magnet.

The greater the speed, the greater the magnitude of the emf, and the emf is zero when there is no motion. The method of inducing an emf used in most electric generators is shown in Figure 3. A coil is rotated in a magnetic field, producing an alternating current emf, which depends on rotation rate and other factors that will be explored in later sections. Note that the generator is remarkably similar in construction to a motor another symmetry. Figure 3. Rotation of a coil in a magnetic field produces an emf.

To increase the induced voltage:. A bar magnet rests outside a wire coil connected to an ammeter showing no current. The magnet moves into the coil of wire and the ammeter registers positive current flow. For a wire carrying a current, I , where a length l of the wire is in the magnetic field, this becomes:. What happens when a wire is placed within a magnetic field? Physics Magnetism Magnets and Magnet Fields. David G. Jan 27, Explanation: When charged particles are stationary in a magnetic field, no force acts on them.

Connect and share knowledge within a single location that is structured and easy to search. If a magnet moves near a coil, it generates a changing flux which generates current due to Faraday's Law. Clearly there is no flux when we consider a straight wire, but it seems to me that a current should still form. Each electron in the wire behaves like a small magnetic dipole since they rotate around the nucleus.

It feels wrong because neither the magnet nor the wire are moving, but I can't see why there shouldn't be a current.

If a wire, coiled or not, is moving through a magnetic field, or the field moves near the wire, some current can be generated.

Coils will have more wire in the magnetic flux and produce more current. If both the magnetic field and the wire are stationary to each other, no current will be produced.

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