The generation of induced current, the conditions under which the induced current is generated

1. The magnetic flux acting on the conductor changes when the conductor rod moves in the magnetic field, in fact, it is the same, or the magnetic flux changes and the conductor is fixed; Either the magnetic flux is fixed and the conductor moves; Either both, all three conditions can produce induced EMF.

2. The current must have a closed loop. There are no isolated current sources.

3. Area, frame, if your magnetic flux is fixed and the conductor is not moving, it must have no current. Your conductor is moving, and the two conductor current directions form a loop.

1. You can understand it this way, suppose that the straight conductor is one side of a virtual plane, and when the other three sides do not move, moving this conductor will reduce the area of this virtual plane, and the magnetic flux passing through will be less. Magnetization.

2. The current is only generated in the closed loop, and the situation you mentioned is only the induced electromotive force generated on the straight wire, but because the loop is not formed, there will be no current.

3。You can explain this problem as a whole and individually, you can see the two sides of the cutting magnetic field lines as two power sources, draw a diagram to see, it is equivalent to two dry batteries in parallel, in fact, there is no current generated. Although there is an induced electromotive force on each side, there is no current flowing in the loop, so it does not violate the theory of "variable magnetism".

The book says that the change in magnetic flux is a necessary condition for the generation of induced electromotive force, and that the induced current must be a closed loop, but the microscopic explanation of the current generation is that there must be a directional movement of ions.

1.In this case, if it is a conductor rod cutting in a magnetic field, the movement of magnetic inductance lines will produce induced electromotive force, and only 'magnetism' will produce induced electromotive force???

2.From 1 question, if the conductor rod moves from the original uniform straight line to the left to accelerate to the left linear motion, the original uniform motion will cause qvb=qe to maintain balance due to the stable potential difference between the two ends of the conductor rod, but now because the speed of the electron moving to the left gradually increases, from f lo = qvb, it can be seen that f lo increases, and at any time the f lo in the conductor qe, so that the electrons will move directionally, will not form a current, In other words, not only will a current be formed in the event of a disconnected circuit, but will there be an isolated current source?

3.In the same way, if the conductor rod in 2 is replaced with a rectangular wireframe, because the rectangular wireframe will have an accelerated motion of cutting magnetic inductance lines on both sides, the same reason is that the two conductors will induce current, but the magnetic flux in the entire rectangular wireframe does not change, so why is there a current???

Confused???

If there is a change in the magnetic flux passing through a closed circuit, then an induced current is generated in the closed circuit. That is, there are two conditions for generating induced current: 1. The circuit is closed.

2. A part of the conductor cuts the magnetic inductance line in the magnetic field. When the conductor is stationary in the magnetic field or moves parallel to the magnetic inductance lines, the magnetic flux does not change, so no current is induced in the closed loop, no matter how strong the magnetic field is.

The concept of induced current.

Induced current refers to the induced electromotive force in a closed loop. When a part of the conductor in a closed loop moves in a magnetic field to cut magnetic inductance lines, the magnetic flux in the closed loop changes, and the resulting electromotive force drives the flow of electrons, eventually forming an induced current. A part of the conductor of the closed circuit cuts the magnetic inductance line in the magnetic inductance line, and the current generated is called the induced current, which is one-sided, and the conductor can also generate the induced current without cutting the magnetic inductance line.

How to determine the induced current.

Use the right-handed rule, i.e.: extend your right hand so that your thumb is perpendicular to the other four fingers and all in the same plane as your palm; Let the magnetic wire enter from the palm of the hand and point the thumb in the direction of the wire movement, then the direction of the four fingers is the direction of the induced current.

The condition under which the induced current is generated is the cutting of the magnetic field lines.

1. Closed conductor. 2. The magnetic flux in the closed conductor changes.

The current in which the magnetic field generated in the original magnetic field of a closed loop prevents the change of the magnetic flux of the original magnetic field is called an induced current.

When a conductor placed in a variable magnetic flux closes into a loop, the electromotive force drives the flow of electrons, resulting in an induced current (induced current).

Generally speaking, when a part of the conductor of the closed loop moves in the magnetic field to cut the magnetic inductance line, the magnetic flux in the closed loop will change, and the induced electromotive force will be generated in the closed loop, thus generating an electric current, which is called induced current.

Conditions for the generation of induced current: magnetic field, motion (motion of cutting magnetic induction wires), and conduction loop.

Through the Oster experiment, which involves the introduction of magnetism into magnetism, and then the use of experiments to induce electric currents and what factors are related to the conditions and direction of the current, Faraday's electromagnetic induction phenomenon was discovered by chance, and at the same time, the story of Coraton running out of opportunity to enhance the interest of physics learning.

The last small toy generator can also be used as an electric motor, reflecting the interconnectedness and wonder of physics. The current generated by the magnetic field in the original magnetic field of a closed loop that prevents the change of the magnetic flux of the original magnetic field is called an induced current, and it is a circuit in which a conductor placed in the changing magnetic flux is closed into a loop, and the electromotive force drives the flow of electrons to form an induced current (induced current).

Generally speaking, when a part of the conductor of the closed loop moves to cut the magnetic inductance line in the magnetic Zheng Wang slag field, the magnetic flux in the closed loop must change, and the induced electromotive force is generated in the closed loop, thus generating an electric current, which is called induced current.

Judgment of direction:

Judgment method: Use the right-handed rule, that is: extend the right hand so that the thumb is perpendicular to the other four fingers, and all are in the same plane as the palm; Let the magnetic wire enter from the palm of the hand and point the thumb in the direction of the wire movement, then the direction of the four fingers is the direction of the induced current.

The direction in which the induced current is affected by the direction of coil rotation and the direction of the magnetic field.

In electromagnetism, the right-hand rule mainly determines the direction independent of the force. It can also be used to determine the direction of the magnetic field generated by the induced current according to Lenz's law, and then use the right-hand spiral rule to judge the direction of the current ** circle.

Note: To increase the cutting speed, theoretically speaking, the larger the speed, the better, but due to the large inertia of the meter pointer (especially for large demonstration meters), when the cutting speed is too large, the pointer will not have time to respond, and the induced current shown by the meter will be reduced. Therefore.

Attention should be paid to selecting the appropriate cutting speed to achieve a better demonstration effect.

Conditions under which the induced current is generated: frontal ridge

One is that the circuit is closed and on, and the other is that the magnetic flux through the closed circuit changes. (If a condition is missing, no induced current will be generated).

When a conductor cuts magnetic field lines to the left or right, the area enclosed by the closed circuit changes, and so does the magnetic flux passing through that area. The cause of the induced current in the conductor.

It can be attributed to a change in the magnetic flux passing through a closed circuit. It can be seen that whenever the magnetic flux passing through the closed circuit changes, an induced current is generated in the closed circuit. This is the condition under which the induced current is generated.

Introduction to Induced Current:

The two ends of the conductor are connected to the two binding posts of the ammeter to form a closed circuit, when the conductor moves left or right in the magnetic field and cuts the magnetic field lines, the pointer of the ammeter is deflected, indicating that a current is generated in the circuit The current thus generated is called induced current.

The direction of the induced current:

When the conductor moves to the left or to the right, the deflection direction of the ammeter needle is different, which indicates that the direction of the induced current is related to the direction of the conductor's movement. If the direction of the conductor's motion is kept unchanged and the two magnetic poles are reversed, the direction of the magnetic field lines is changed.

As you can see, the direction of the induced current also changes. It can be seen that the direction of the induced current is related to the direction of the conductor's motion and the direction of the magnetic field lines.

**: Whether the movement of a conductor rod (part of a closed loop) in a magnetic field generates an induced current (a change in the magnetic flux by the movement of the conductor rod relative to the magnetic field).

1. Experimental phenomenon: when the conductor rod is stationary or parallel to the magnetic inductance line movement, there is no induced current: when the conductor rod cuts the magnetic inductance line movement, there is an induced current.

2. Conclusion: When some conductors in the closed circuit cut the magnetic inductance line, the induced current will be generated in the circuit.

3. Analysis: The strength of the magnetic field remains unchanged, but the movement of some conductors to cut magnetic inductance lines changes the magnetic field area surrounded by the closed conductor loop, and the magnetic flux through the loop changes and induces current.

The current is flowing, and the loop must be closed. Only when there is still an equivalent power supply in the circuit can there be a current.

Therefore, the conditions for generating induced current are: 1. There is a closed loop. (Provide a current path). 2. Part of the conductor cuts the magnetic inductance line (this is to provide power supply).

Or to use Faraday's law of electromagnetic induction: as long as the magnetic flux passing through a closed loop changes, there is an induced current in the loop.

The second narrative is synthetic, and the first is a special case.

If you don't understand something, you can ask it at any time.

Please adopt it in time. If you have any questions, ask them in a timely manner.

The condition for the induced current to be generated is that the magnetic flux passing through the closed loop changes, and the induced current is generated in the loop.

Specifically, there are two cases: one is that in a stable magnetic field, part of the conductor of the closed loop cuts the magnetic field lines. The second is a change in the strength of the magnetic field passing through the closed loop.

Induced current is a current in which the magnetic field generated in the original magnetic field of a closed loop prevents a change in the magnetic flux of the original magnetic field.

Generation conditions: As soon as the magnetic flux passing through the closed circuit changes, an induced current is generated in the closed circuit. Therefore, "a part of the conductor of a closed circuit cuts the magnetic inductance line in the magnetic inductance line, and the current generated is called the induced current" is one-sided, and the conductor can also generate the induced current without cutting the magnetic inductance line.

**Conditions under which the induced current is generated.

The power of the induced current refers to the power of the work done by the current generated by the alternating magnetic field inside the magnetically conductive object to overcome the internal resistance of the object. Some are useful, such as induction cookers, which rely on induction currents to generate heat; Some are useless, like the heating of the transformer core.

The current in which the generated magnetic field prevents a change in the original magnetic flux is called an induced current.

A part of the conductor of a closed circuit moves in a magnetic field to cut magnetic inductance lines.

The induced current is the current generated by a metal conductor under the action of an alternating magnetic field.

To put it bluntly, the current generated by the magnetic field that prevents the change in the original magnetic flux is called an induced current.

In layman's terms, it means that two magnetic fields are on a plane, and the magnetic field blocks the current produced by the variable of the other magnetic field, which we call the induced current.

The changing magnetic field produces an induced current.

When a part of the conductor of a closed loop moves in a magnetic field to cut magnetic inductance lines, the magnetic flux in the loop changes, resulting in an electric current.

Analysis: The conditions for generating induced currents are.

The magnetic flux passing through a closed circuit changes.

The magnet is at a distance from the ring (the magnetic inductance line passes through the aluminum ring).

But when not moving. The magnetic flux passing through the ring is constant, so there is no induced current.

When the magnet descends or rises at a certain velocity, the magnetic flux passing through the ring changes.

Therefore, an induced current is generated.

**Conditions under which the induced current is generated.