Junior high school physics simple motor the more detailed the better, very much need thanks

This is the principle of the electric motor experiment. Principle: The energized coil rotates under force in a magnetic field.

If the patent leather at both ends of the coil is scraped off. Then the coil will only rotate back and forth in the magnetic field, that is, it will rotate back and forth, and it will not rotate 360°. If you scrape it halfway, it will keep turning.

Because the patent leather is insulated, when the coil turns to a certain angle, the patent leather contacts with the wire, the current in the coil disappears, and the magnetic field disappears, at this time the coil is out of the balance position, but due to inertia, the coil will continue to rotate a little angle, when the balance position is crossed, the coil is in contact with the wire, continues to be energized, and rotates by force to rotate in this way. Using this principle, electric motors are made such as electric fans, electric cars and so on.

Scrape off all the patent leather and the coil will pass back and forth Reason: Since there is no patent leather coil, the two ends will always be in contact with the wire and will always be energized. Because the energized coil is subjected to an upward force all the time in the magnetic field.

The coil rotates with an upward force, and when the coil crosses the equilibrium position, it is subjected to the force of the magnetic field, so it turns in reverse, and so on and not rotate 360°.

The way to change the direction of rotation of the coil is to change the direction of the current (i.e. to switch the positive and negative poles of the power supply or to change the direction of the magnetic field).

Instead of scraping off the general patent leather, as was the case with the coils in the test, the real motor was fitted with a device that could automatically change the direction of the current: the commutator. When the coil crosses the equilibrium position, the commutator changes the direction of the current, so that the coil continues to rotate.

Pure hand lookout.

Push the coil reason: the coil is in the equilibrium position.

The reason why the coil keeps rotating: the other end scrapes off the half-circumferential patent leather and puts the coil on the bracket, which is not energized for half a circumference, relying on inertia.

To change the direction of rotation of the coil: change the magnetic pole or change the positive and negative poles of the battery.

The coil does not rotate in the equilibrium position.

The current is subjected to the action of force in the magnetic field, when it goes to the half turn with enameled wire, there is no current in the coil, due to inertia, the coil continues to rotate, when there is a half turn to the bare wire, there is a current in the coil, and the magnetic field continues to act on the coil. So that the coil keeps turning.

Invert the positive and negative poles of the battery.

The working principle of the motor is the effect of the magnetic field on the current force, which makes the motor rotate. The electric motor converts electrical energy intoMechanical energyA piece of equipment. It is a magnetoelectric dynamic rotation torque that uses an energized coil to generate a rotating magnetic field and acts on the rotor squirrel cage to close the aluminum frame to form a magnetoelectric dynamic rotational torque.

The role of electric motor fields:

Feeling the action of the electric field, the positive charge will accelerate in the direction of the electric field; But feel the action of the magnetic field, according to the left-handed rule.

The positive charge will bend in the direction perpendicular to the velocity v and the magnetic field b (in detail, the left-handed rule is applied, when the four fingers refer to the direction of the current, the magnetic inductance lines.

When passing through the palm of the hand, the direction of the thumb is the Lorren Cong Clang.

direction). If a charged particle is injected into a uniform magnetic field, its velocity is at an angle of 0< <2 to the magnetic field, and the particle will move in an equidistant spiral (a uniform straight line motion in the b direction).

and the sum of uniform circular motion perpendicular to b).

The Lorentz force applies to both macroscopic and microscopicly charged particles. Ampere force exerted on a current element in a magnetic field.

It is the macroscopic surface permeation of the Lorentz force on which the moving charge is subjected.

Motor Principle:

1. The electric machine is a kind of rotary electric machine, which converts electrical energy into mechanical energy, which mainly includes an electromagnet winding or distributed stator winding and a rotating armature or rotor to generate a magnetic field. Under the action of the rotating magnetic field of the stator winding, there is an electric current passing through the effective side of the stator winding and being rotated by the magnetic field.

2. According to the principle of reversibility of the motor, if the motor does not change in its structure, the motor is used as a motor or as a generator. It is a machine that converts electrical energy into mechanical energy. Usually the working part of the electric flap motor is rotated, and this kind of motor is called a rotor motor; There are also those that do linear motion, which are called linear motors.

The principle of the generator is that each cylinder works in a certain order, and the thrust acting on the piston becomes a push through the connecting rodCrankshaftThe force of rotation, which drives the crankshaft to rotate.

A generator is the conversion of other forms of energy into electricity. The generator component is the stator.

Rotors, end caps and bearings. Generators have a wide range of uses in industrial and agricultural production, national defense, science and technology, and daily life. There are many forms of generators, but their working principles are based on the laws of electromagnetic induction.

and the law of magnetic force of electric acres. Therefore, the general principle of its construction is to use the magnetic and conductive materials of the suitable material to form a magnetic circuit and circuit for electromagnetic induction with each other, so as to generate electromagnetic power, and finally achieve the purpose of energy conversion.

What to talk about:

1. Teaching objectives, knowledge and skills: through experiments, know the strong effect of magnetic field on energized wires, and know that the direction of force is related to the direction of current and magnetic field. Through experimental observation, we know that the magnetic field can rotate the energized coil, understand the working principle of the commutator, and understand the structure, working principle and energy conversion of the DC motor.

2. Process and MethodExperience**Process: Cultivate experimental operation skills and experimental operation interests: emotional attitudes and valuesThrough experiments, "let the coil turn", and experience the joy of overcoming various difficulties and successfully solving physical problems.

3. Teaching difficulties: This section includes two parts: the effect of the magnetic field on the energized wire and the basic structure of the motor.

The working principle of the motor is that the magnetic field has a strong effect on the energized wire, and it is the basis for learning the motor to know the strong effect of the magnetic field on the energized wire through experiments.

In the experiment, students are guided to carefully observe the experiment, analyze the experimental phenomenon, and come to the conclusion that the energized wire is affected by the force in the magnetic field, and the direction of the force is related to the direction of the current and the direction of the magnetic inductance line: the motor is widely used in practice, but the students are not familiar with its internal structure, and the force movement in the magnetic field through the coil understands how the actual motor works.

The rotor of the motor can rotate continuously because the commutator is installed, the coil turns to the balance position, changes the direction of the coil cow current, so that the coil can rotate continuously, and knowing the role of the commutator is the key to understanding the working principle of the motor.

Electric motor applications

Among the various motors, the most widely used is the AC asynchronous motor (also known as the induction motor). It is easy to use, reliable in operation, inexpensive and firm in structure, but the power factor is low, and the speed regulation is also more difficult. Synchronous motors are commonly used for large-capacity and low-speed power engines.

Synchronous motors not only have a high power factor, but also have nothing to do with the load size, but only depend on the grid frequency. The work is more stable. DC motors are often used in occasions that require wide-range speed regulation.

But it has a commutator, complex structure, **expensive, difficult to maintain, and not suitable for harsh environments.

After the 70s of the 20th century, with the development of power electronics technology, the speed regulation technology of AC motors has gradually matured, and the equipment has been gradually reduced, and it has begun to be applied. The maximum output mechanical power that the motor can bear under the specified working system (continuous, short-time operation system, intermittent cycle operation system) without causing the motor to overheat is called its rated power, and it is necessary to pay attention to the provisions on the nameplate when using.

Physics in the third year of junior high school (Shanghai Science and Technology (Cantonese Education) Edition) "The Principle of Motor Rotation".

When a wire is placed in a magnetic field, if the wire is connected with a current, the wire will cut the magnetic field line to make the wire move. A device in which an electric current enters the coil to generate a magnetic field, and a device that uses the magnetic effect of the current to make the electromagnet rotate continuously in a fixed magnet can convert electrical energy into kinetic energy. Interacts with a permanent magnet or a magnetic field generated by another set of coils to generate power.

There are many types of electric motors, and in terms of basic structure, their composition is mainly composed of stator and rotor. The stator is stationary in space, while the rotor rotates around the shaft and is supported by bearings. There will be a certain air gap (air gap) between the stator and the rotor to ensure that the rotor can rotate freely.

The casing (field yoke) needs to be made of a material with high permeability and is to be used as a magnetic circuit.

The principle of a DC motor is that the stator does not move, and the rotor moves in the direction of the force generated by the interaction. In the AC motor, the stator winding coil is connected with alternating current, which generates a rotating magnetic field, and the rotating magnetic field attracts the rotor to rotate together.

Classify. 1. DC motor: using permanent magnets or electromagnets, brushes, commutators and other components, the brushes and commutators touch the external DC power supply, continuously to the rotor coil, and change the direction of the current in a timely manner, so that the rotor can continue to rotate in the same direction.

Operation of direct current electric motors are based on the principle that when a current-carrying conductor is placed in a magnetic field, the conductor is subjected to a mechanical force.

2. AC motor: The alternating current is passed through the stator coil of the motor, and the surrounding magnetic field is designed to push the rotor at different times and positions to make it run continuously.

3. Pulse motor: The power supply is processed by a digital IC chip and turned into a pulse current to control the motor, and the stepper motor is a kind of pulse motor.

1. The motor is a kind of rotating electric machine, which converts electrical energy into mechanical energy, which mainly includes an electromagnet winding or distributed stator winding and a rotating armature or rotor to generate a magnetic field. Under the action of the rotating magnetic field of the stator winding, there is an electric current passing through the effective side of the stator winding and the ruler is rotated by the magnetic field.

2. According to the principle of reversibility of the motor, if the motor does not have any change in its structure, the motor is used as a motor and can also be used as a generator. It is a machine that converts electrical energy into mechanical energy. Usually the work part of the motor is rotated, and this kind of motor is called a rotor motor; There are also those that do linear motion, which are called linear motors.

Electric motor: An energized conductor is subjected to a force in a magnetic field.

Generator: Electromagnetic induction.

The principle of the electric motor is made by using the force of an energized conductor in a magnetic field.

If the current i, voltage u, and resistor r are of the same circuit, the results calculated by these two methods should be the same. Because p=i 2r can be deduced from Ohm's law p=u 2 r;

p=i^2r（i^2=（u/r^2））=（u/r）^2xr=u^2/r。

You can pass in the questions you don't think you're good at, and see what's wrong.

The principle of the physical motor in the third year of junior high school is as follows:

An electric motor is a device that is capable of converting electrical energy into mechanical energy. It is basically composed of two parts, the stator is a stationary lift, and the rotor can rotate. When an electricity is applied in the stator, a rotating magnetic field is created that acts on the rotor and causes it to start rotating.

This is because the current in the rotor is subjected to a moment by the action of a magnetic field and thus starts to rotate.

The working principle of an electric motor involves a lot of physics, including electromagnetic induction, electromagnetic force, magnetic field, and more. In Grade 9 Physics, the principle and working mode of DC motors are mainly involved. DC motor is one of the most common types of motor, and its basic structure consists of two parts: a stator and a rotor.

Among them, the stator usually consists of a number of coils that are fixed to the motor housing. The rotor, on the other hand, is made of some magnetic material, usually some magnetic cores and copper coils.

When an electric force is applied on the stator, a rotating magnetic field is created that acts on the rotor and causes it to start rotating. The copper coil in the rotor will produce a current due to the action of the magnetic field, and this current will be affected by the magnetic field and generate a moment, so that the rotor will start to rotate. In the process of rotor rotation, because the position of the coil on the rotor is constantly changing, the direction of the current on the rotor will also be constantly changing, so that the direction of rotation of the motor can be guaranteed.

In the process of using the motor, it is necessary to pay attention to some issues, such as the use environment of the motor, the safety of the world combustion use, etc. At the same time, it is also necessary to evaluate and calculate the power, efficiency and other parameters of the motor to ensure its normal operation and maximum efficiency.