Help me list the main points of constant current I got a donkey kick in the head

Key Takeaways:

The key difficulties can be found here**.

1.Knowing that the basic properties of a constant electric field are the same as that of an electrostatic field, the relationship that applies in an electrostatic field is also applicable in a constant electric field.

2.Know what a constant current is, know the unit of current, and understand the relationship between physical quantities such as charge, current, and energizing time.

3.Know that a power source is a device that provides electrical energy, and converts other forms of energy into electrical energy by doing work with non-electrostatic forces. Understand the concept of electromotive force and know that electromotive force and voltage are two different concepts.

4.Understand the concept of resistance and know the physical meaning of the unit of resistance. Understand Ohm's law and where it can be applied. Ohm's law will be used to solve problems in circuits.

5.Know the volt-ampere characteristic curve of the conductor, know the linear and nonlinear components.

6.Understand the connection mode of series-parallel circuits, and master the relationship between current, voltage and resistance of series-parallel circuits.

7.Understand the concept of electrical work, knowing that electrical work refers to the work done by the electrostatic force on a free charge. Knowing the difference and connection between electrical power and thermal power can distinguish between electrical work and thermal work.

Constant current Fundamentals.

The amount of charge passing through a certain cross-section per unit time of a constant current field is referred to as current. i is the flux and does not reflect the flow of current at each point.

Electric current is the regular motion of an electric charge. According to the mechanism of current formation, there are two types of current: conduction current and transport current.

Conduction current is the current formed by the movement of free electrons (or holes) in a conductor or ions in an electrolyte; A transport current is an electric current formed by the movement of electrons, ions, or other charged particles in a vacuum or gas.

The current density is a vector quantity whose direction is the direction of motion of a positive charge and its magnitude is the amount of charge perpendicular to the unit area per unit of time. In isotropic linear conductive media, it is in the same direction as the electric field strength.

The current passing through a section is the flux through the current density of that section.

The electric field is necessary to maintain a constant current.

The constant current field and the constant electric field are interdependent. The current density j is consistent with the electric field strength e direction.

The power supply electromotive force is independent of the presence or absence of external circuits, it is a characteristic quantity that represents the power supply itself. The external electric field generated by the non-electrostatic force in the power supply is not a conservative field.

A constant electric field is a non-dispersed field, and the current lines are continuous.

Outside of the power supply, the constant electric field is no rotation field.

A constant electric field, like an electrostatic field, is independent of time, but it is caused by an applied voltage and can exist in a conductor, whereas an electrostatic field is generated by a stationary charge and cannot be present in a conductor.

A conductor with an infinite electrical conductivity is called an ideal conductor. It is impossible for a constant electric field to exist in an ideal conductor. A medium with a conductivity of 0 that does not have the ability to conduct electricity is called an ideal medium.

The tangential component of the electric field strength at the interface is continuous, and the normal component of the current density is continuous.

Solution: The resistors of the two lamps are:

R1 U1 i1 220 100 €; R2 u2 i2 220 200 ohm.

Then the total resistance of the series circuit is r r1 r2 ohms.

The total current of the series circuit is: I i1 i2 u r 220 amps. (can be omitted).

The ratio of the current of the two lamps: i1:i2 i:i 1:1;

The ratio of the voltage of the two lamps: u1:u2 ir1:ir2 r1:r2 ::1;

The ratio of the actual power of the two lamps: P1:P2 I 2R1:I 2R2 R1:R2 2:1;

The ratio of the actual heat generated by the two lamps in the same time: Q1:Q2 I 2R1T:I 2R2T R1:R2 2:1.

a...according to p=v2(squared) r,pa pb=rb ra

it means'''ra:rb=2:1""

grade 8 physics problems...

Familiarity with the formula is key.

Professional Answer:

Maxwell's theory is more abstract, as you can understand:

The magnetic field is a relativistic effect of the electric field.

A magnetic field is essentially an electric field force.

Just talking about the field generated by the size of the charge, that is the electric field, because the field generated by the motion of the charge is a constant electric field produced by a constant current in the magnetic field, and because the number of charges per unit volume per unit of time is constant, the electric field is constant.

At the same time, a constant magnetic field is also generated, because the current is constant, that is, the speed of the charge is constant, so the magnetic field is constant.

In itself, it is just a nomenclature to distinguish between the two, because it depicts the field of different properties of charges, and the two are not related (one is the amount of charge, the other is due to the motion of the charge, one change does not indicate the other change, and the two are independent).

No, the two currents are not the same.

v ma=543, because there is a loss of dust to take the voltage on the pin ammeter, so the number of voltage representations is large, so the true value should be less than 543

Ohm's law for closing a vertical circuit i=e (r+r) where r represents the total resistance of the external circuit, and the total resistance of the circuit is r+r slip, so it is i=e (r+r+r slip).

i(r+r+rslip)=e

i(r+r)+ir slip=e

i(r+r)=e-u slip.

i=(e-u sliding sh embedded) Fiber Ant(r+r).

In fact, the right side is quite a power supply, and the current direction is opposite to the original current, canceling out the voltage, how can it be understood.

The answer is all 1 ampere.

The difference between the two problems is that in the first problem, both the positive and negative ions are the total amount of discharge on the electrode, so that the current value obtained is the current value of the entire electrolyzer;

The second question asks about the behavior of charged particles on a reference section in the electrolyzer, which may be a section of the entire electrolyzer or just a part of it. Unless otherwise specified, this issue is not relevant to the electrolyzer as a whole.