What is the left handed rule and right handed rule in physics?

The left-hand rule] The left-hand rule is also known as the "motor rule". It is a rule that determines the direction of force on an energized conductor in an external magnetic field. The method of this is:

Extend your left hand so that your thumb is perpendicular to the remaining four fingers and all in the same plane as your palm. Imagine placing your left hand in a magnetic field, so that the magnetic field lines enter the palm perpendicularly, and the remaining four fingers point in the direction of the current, and the direction of the thumb is the direction of the force exerted by the magnetic field on the current. The right-hand rule is also known as the "generator rule".

A rule that determines the direction of the induced current in a conductor as it moves in a magnetic field. Extend the stone hand so that the thumb is perpendicular to the other four fingers and all in the same plane as the palm. Suppose you put your right hand into a magnetic field, so that the magnetic field lines enter perpendicular to the palm of your hand, so that your thumb points in the direction of the conductor's movement, and the direction of the other four fingers is the direction of the induced current.

Right-hand spiral rule] indicates the rule of the relationship between the direction of rotation of the right-hand spiral shank and the direction of spiral advancement. For example, in the Cartesian right-handed coordinate system, the direction of rotation from the x-axis through 90° to the y-axis is the direction of rotation of the handle, and the z-axis follows the forward direction of rotation. Another example is when the angular velocity is expressed by vectors, if the direction of rotation is along the direction of rotation of the screw handle, the forward of the spiral is generally used with the left hand, and the other is the right hand.

In the circuit, the current direction and the magnetic pole current direction in the solenoid coil are upward, the left n right s current direction is downward, and the left s right n

1. The left-hand rule.

The left-hand rule, which can be called the "motor rule", is the law that determines the direction of the force of the energized wire in the magnetic field, which is the force of the magnetic field on the electric current, or the force of the magnetic field on the moving charge. The content is: put the left hand into the magnetic field, so that the direction of the four fingers is the same as the direction of the current in the wire, then the direction of the thumb is the direction of the force.

Whether it is a DC generator or an alternator, they all work on the same principle, the difference is that a DC generator has a commutator, while an alternator does not have a commutator. It is suitable for situations where the direction of the current is perpendicular to the direction of the magnetic field.

2. The right-hand rule.

The right-hand rule, which can be called the "generator rule", is the law for judging the direction of the magnetic inductance line around the energized wire or the north and south poles of the solenoid, the direction of the magnetic field, the movement of the cutting magnetic inductance line, and the direction of the electromotive force, which is the direction of the induced current.

The content is: hold the wire with your right hand and point your thumb in the direction of the current, then the direction of the four fingers around is the direction of the magnetic line. Hold the solenoid with your right hand and bend your four fingers in the direction of the current in the solenoid, so that the end of your thumb is the north pole of the solenoid.

It is only suitable for judging the movement of some conductors in a closed circuit to cut magnetic inductance lines.

I will give you a method of memorization: the main thing depends on whether it is electricity or force, you can remember it like this: the tail of electricity is hooked to the right (the last stroke is to the right, therefore, the right hand is the rule of judging the generation of electricity, the left stroke of the force is the apostrophe, to the left, and the left hand is the rule of judging the generation of force), I learned it in high school, it is very useful to me, I hope it will help you.

The right-hand rule: one is Ampere's rule, hold the solenoid with your right hand, let the four fingers point to the direction of the current in the solenoid, then the end of the thumb is the n pole of the solenoid. Second, it is suitable for the generator palm is the direction of the magnetic field, the thumb is the direction of the object movement, and the finger is the direction of the current, and determines the direction of the dynamic electromotive force generated in the conductor when the conductor cuts the magnetic inductance line and moves.

Note: The object is a straight wire, and the velocity v and magnetic field b must be perpendicular to the wire, and v and b must be perpendicular to each other, and the right-hand rule cannot be used to determine the direction of the induced electromotive force.

Left-handed rule: The relationship between the direction of the magnetic field, the direction of the current, and the direction of the force exerted by the magnetic field on the current can be expressed by the "left-handed rule". Extend your left palm so that your thumb and four fingers are vertical.

Put the left palm into the magnetic field, so that the magnetic inductance line passes from the palm of the hand to the back of the hand (that is, the palm of the hand is opposed to the n poles), and make the four fingers point in the direction of the current, and the thumb refers to the direction of the current by the magnetic field.

Electromagnetism. Oersted's experiment shows that there is a magnetic field around the energized wire, and the direction of the magnetic field is related to the direction of the current, which is called the magnetic effect of the current.

The magnetic field on the outside of an energized solenoid is very similar to that of a bar magnet. The two ends of the energized solenoid are equivalent to the two poles of a bar magnet, and their magnetic properties can be determined experimentally by pointing the small magnetic needle, the external magnetic field of the energized solenoid starts from the n pole and returns to the S pole, and the inside points from the S pole to the n pole. With amperdine, the n-pole of the solenoid can be determined by the direction of the current.

Magnetism generates electricity. The phenomenon of electric current generated due to the movement of a conductor in a magnetic field is an electromagnetic induction phenomenon, and the current generated is called induced current.

Conditions for induced current: When a part of the conductor of a closed circuit moves to cut magnetic inductance lines in a magnetic field, an induced current is generated in the conductor. The phenomenon of electromagnetic induction is the principle of generators.

The left-handed rule in physics is the law that determines the relationship between the direction of the ampere force f (or motion), the direction of the magnetic induction intensity b, and the current i of the energized conductor rod when it is in a magnetic field. The left-handed law is a simplified form of two vector crosses multiplying the direction of the force.

The left-handed rule and the right-hand rule appear in the electromagnetism section of high school physics textbooks, and are one of the key points of the electromagnetism part. Straighten the index, middle, and thumb of your left hand so that they are perpendicular to each other in space. The direction of the index finger represents the direction of the magnetic field (from n to s), the middle finger represents the direction of the current (from positive to negative), and the direction of the thumb is the direction of the force.

When using it, it can be remembered that the middle finger, index finger, and thumb refer to "electricity, magnetism, force".

The rules in physics regarding the left hand and the right hand are as follows:

1. The rule of the left hand:

1. It is used to determine the direction of force of the energized straight wire in the magnetic field;

2. The method used to judge the direction of force of charged particles in the magnetic field: stretch out the left hand, so that the thumb is perpendicular to the other four fingers, and are in the same plane as the palm, let the magnetic inductance line penetrate the palm, and make the four fingers point to the direction of the current, and the direction pointed by the thumb is the direction of the ampere force on the energized wire.

2. The right-hand rule:

1. When the straight wire used to judge the movement cuts the magnetic inductance line, the direction of the electromotive force is induced;

2. Method: Stretch out the right hand, so that the thumb is perpendicular to the other four fingers, and are in the same plane with the palm, the direction of the thumb is the direction of the straight wire, and the direction of the four fingers is the direction of inducing electromotive force.

3. Ampere's rule:

1. Judge the magnetic field around the energized straight wire;

2. Judge the north and south poles of the energized solenoid;

3. Determine the direction of the toroidal current magnetic field;

4. Method: Hold the energized wire with the right hand, so that the direction of the straight thumb is consistent with the direction of the current, and the direction of the curved four fingers is the surrounding direction of the magnetic inductance line; Hold the energized solenoid in your right hand and the direction of your four fingers is the same as the direction of the current, and the direction of your thumb is the direction of the North Pole.

The rules in physics regarding the left hand and the right hand are as follows:

1. The rule of the left hand:

1. It is used to determine the direction of force of the energized straight wire in the magnetic field;

2. The method used to judge the direction of force of charged particles in the magnetic field: stretch out the left hand, so that the thumb is perpendicular to the other four fingers, and are in the same plane as the palm, let the magnetic inductance line penetrate the palm, and make the four fingers point to the direction of the current, and the direction pointed by the thumb is the direction of the ampere force on the energized wire.

2. The right-hand rule:

1. When the straight wire used to judge the movement cuts the magnetic inductance line, the direction of the electromotive force is induced;

2. Method: Stretch out the right hand, so that the thumb is perpendicular to the other four fingers, and are in the same plane with the palm, the direction of the thumb is the direction of the movement of the straight wire, and the direction of the four fingers is the direction of the induced electromotive force.

3. Ampere's rule:

1. Judge the magnetic field around the energized straight wire;

2. Judge the north and south poles of the energized solenoid;

3. Determine the direction of the toroidal current magnetic field;

4. The old method: hold the energized wire with the right hand, so that the direction of the straight thumb is consistent with the direction of the current, and the direction pointed by the curved four fingers is the surrounding direction of the magnetic inductance line; Hold the energized solenoid in your right hand, and the direction of your four fingers is the same as that of the current, and the direction of your thumb is the direction of the North Pole.

The four fingers of the right hand are merged except for the finger, and the finger is perpendicular to the other four fingers, and the four fingers are held from the direction of the A vector to the direction of the B vector, and the direction of the Mu finger is the direction of the product of the A and B vector vectors. That is, the direction of the AB vector product is perpendicular to the plane determined by the AB vector.

Vector product, also known as outer product and cross product in mathematics, and vector product and cross product in physics, is a binary operation of vectors in vector space by the core ridge. Unlike the dot product, it results in a vector rather than a scalar. And the cross product of the two vectors is perpendicular to the perpendicular to the permeability vector of these two modifications.

It is also widely used, often in physics, optics and computer graphics.

The right-hand rule in physics: Hold the solenoid with your right hand so that your four fingers are bent in the same direction as the solenoid's current, and the end of your thumb is the n pole of the magnetic field generated by the energized solenoid. For the magnetic field of a straight current, the thumb points to the direction of the current, and the direction of the curved four fingers is the direction of the magnetic inductance line (the direction of the magnetic field or the direction of the North Pole of the small magnetic needle or the direction of force on the small magnetic needle).

Later, it was generalized to mathematical vectors.

The right-hand rule is used in electromagnetism to determine the direction of the force independent. If it's about force, it's all about the left-handed rule. That is, the left-handed rule is used for force, and the right-hand rule is used for others (generally used to determine the direction of the induced current).

A general term for the electrical and magnetic properties of matter. Such as electromagnetic induction, electromagnetic waves and so on. Electromagnetism was discovered by the Danish scientist Oster. The cause of electromagnetic phenomena is that the movement of electric charges produces fluctuations and forms a magnetic field, so all electromagnetic phenomena are inseparable from electric fields.

Physical application. A rule that determines the direction of the induced current in a wire moving in an external magnetic field, also known as the motor rule. It is also the law for judging the relationship between the direction of the induced current, the direction of the conductor movement, and the direction of the magnetic field lines.

The flat hand shape is suitable for the generator palm is the direction of the magnetic field, the thumb is the direction of the object movement, and the finger is the direction of the current, to determine the direction of the dynamic electromotive force generated in the conductor when the conductor cuts the magnetic inductance line.