Electrostatic force does positive work, electric potential energy decreases, why does kinetic energy

After reading "Berry Sprout", I found that she was still quite meticulous in her consideration, and indeed the electrostatic force does positive work, and the electric potential energy decreases, this sentence is true, not false at all; But whether the kinetic energy increases depends on the subject of your study.

Generally speaking, for charged particles that can ignore gravity, the electric field force does positive work, the electric potential energy decreases, the kinetic energy increases, and the electric potential energy is only converted into kinetic energy. If gravity is a particle, then the electric potential energy is not only converted into kinetic energy, it may be converted into gravitational potential energy, and of course it may even be converted only into gravitational potential energy, but not kinetic energy [depending on the known conditions given in the question].

If the landlord is talking about charged particles that can ignore gravity, then the sentence you asked is correct.

According to the conservation of energy, the reduced electric potential energy is all converted into kinetic energy.

If you really can't use the kinetic energy theorem: w outside = ek2-ek1 electrostatic force to do positive work, w is positive, ek2-ek1>0, so the kinetic energy increases.

Hope mine is helpful to you.

Just learned. Kinetic energy does not necessarily increase.

If there is only an electrostatic force.

If you do work, the kinetic energy must increase.

If there is not only electrostatic force, but also other work done, then the kinetic energy does not necessarily increase.

Reason: The increment of kinetic energy represents the resultant external force.

Do the right work. With other work, the potential energy may be converted into other energy.

Because in the electric field, mechanical energy.

Electric potential energy is a fixed value, and mechanical energy is divided into gravitational potential energy.

and kinetic energy, if there is gravity doing work, then part of the electric potential energy should be converted into gravitational potential energy, not all kinetic energy.

If there is a force other than electric potential energy to do work, the electric potential energy will be converted into more than kinetic energy.

Upstairs is supported, and this can be compared with the work done by gravity. There are some issues that need to be paid attention to the positive and negative.

The power supply is not internalElectrostatic forceThe reason for the increase in the potential energy of the work done: this is the same as overcoming the gravitational force to do the work that makes the objectGravitational potential energyEnergy addition is a truth, and its essence is to convert other forms of energy into electrical energy.

When learning Ohm's law of closed circuits, inside the power supply, when the action of the resistor is not considered, the kinetic energy of the charge remains unchanged under the condition of constant current, the algebraic sum of the work done by the non-electrostatic force and the electrostatic force is 0, the electrostatic force does negative work, and the work of the non-electrostatic force is equal to the work of overcoming the electrostatic force, so the work of the non-electrostatic force is equal to the increase of the potential energy.

Chemical electromotive force.

Dry cell batteries, coin cell batteries.

The non-electrostatic force of the battery is a chemical action associated with the dissolution and deposition process of ions, and the size of the electromotive force depends on the type of chemical action, and has nothing to do with the size of the power supply, such as the dry electric filial piety socks pool whether No. 1, No. 2, No. 5 electromotive force is volt. Batteries that generate chemical electromotive force are called chemical cells or electrochemical batteries, for example: copper-zinc primary batteries.

The electrolyte solution is copper sulfate.

When doing positive work, the angle between the force and the displacement is an acute angle, and this force can be decomposed into.

The force perpendicular to the direction of displacement (changing the direction of velocity) and the same force as the direction of velocity (increasing the magnitude of the velocity).

So the kinetic energy will increase.

When doing negative work, the angle between force and displacement is obtuse.

This force can be broken down into.

A force perpendicular to the direction of displacement (changing the direction of velocity) and a force opposite to the direction of the brightness velocity, (making the magnitude of the velocity smaller).

So the kinetic energy will decrease.

The electric field force does positive work, the electric potential energy decreases, the electric field force does negative work, the electric potential energy increases, the direction of the positive charge in the electric field is consistent with the direction of the field strength, so the positive charge is along the direction of the field strength, the electric potential energy decreases, and the negative charge is forced in the direction of the electric field and the field strength is opposite, so the negative charge is along the direction of the field strength, the electric potential energy increases, but the electric potential decreases along the direction of the field strength.

The relationship between electric potential energy, electric field force, and work is very similar to the relationship between gravitational potential energy, gravity, and work.

e=mgh, gravity does hail is the first positive work, and the gravitational potential energy decreases.

The original number of factors of electric potential energy is that the electric field force has the ability to do work, and all potential energy laws are almost the same, the electric field force is doing work, the electric potential energy is decreasing, the electric field force is negative work, and the electric potential energy is increasing, in the process of doing positive work, the electric potential energy is converted into other forms of energy through the form of work, so the electric potential energy is reduced.

The positive work done by the electrostatic force = the amount of decrease in the potential energy, and the negative work done by the electrostatic force = the amount of increase in the potential energy.

1) Look at the angle between the electric field force and the displacement direction of the charged particles, less than 90 degrees is positive work, and more than 90 degrees is negative work;

2) Look at the angle between the electric field force and the velocity direction of the charged particle, less than 90 degrees is positive work and more than 90 degrees is negative work;

3) Look at the change of electric potential energy, the electric potential energy increases, the electric field force does negative work, the electric potential energy decreases, and the electric field force does positive work.

If the electric field force does positive work, then the electric potential energy decreases.

The concept of electric potential energy is actually the ability of the electric field force to do work, as long as it is potential energy, then it is understood in this way. The field force and potential energy of the electric imitation chain are converted to each other, and if one increases, then the other decreases. In the process of doing positive work in the electric field, the energy of the electric potential energy is converted into other energy, so the electric potential energy decreases.

E=mgh, if the gravitational potential energy is to increase, then the gravitational force must do negative work. Because energy is always conserved, it is just a conversion from one energy to another. The first is to look at the angle between the electric field force and the displacement direction of the charged particle, just like judging whether an object does positive or negative work, less than 90 degrees is positive work, and vice versa.

The first two types of Shinsun are from the point of view of speed. If the velocity of the particle decreases, it is negative work, and vice versa. The third is from the perspective of energy transformation. The energy must be conserved, and the electric potential energy increases, then the electric field force must do negative work, and vice versa.

The interaction between the charges takes place through an electric field. As long as there is an electric charge, there is an electric field around the charge, and the basic property of the electric field is that it has a strong effect on the charge placed in it, and this force is called the electric field force. The magnitude of the electric field force can be calculated by Coulomb's law or by other formulas.

Because of the law of conservation of energy, the electric field force does positive work, the positive charge decreases from high potential to low potential to positive work, and the corresponding negative charge decreases from low potential to high potential, and the electric potential energy also decreases, so the electric potential energy is reduced.

Energy is neither created nor disappeared out of thin air, it simply transforms from one form to another, or from one object to another, while the total amount of energy remains the same. The law of conservation of energy is one of the basic laws of universal fiber reduction in nature.

Forces other than the electric field force do positive work, which means that there is an external force that increases the energy of the charged object.

Here we will say that the sum of the energy possessed by the charged object in the electric field = the sum of kinetic energy and electric potential energy.

Therefore, other forces other than the electric field force do positive work, and the sum of kinetic energy and electric potential energy becomes larger.

The electric field force does work on a charged object, which is only the conversion between kinetic energy and electric potential energy, and its sum is unchanged.