On the question of physical electric potential and electric potential energy

The electrostatic force is the force by which the positive charge and the negative charge attract each other, while the work done by the electrostatic force is the movement of the charge by a certain distance under the action of attraction (if the positive charge is regarded as a movable charge and the negative charge is fixed, then the positive charge moves a distance under the attraction of the negative charge, that is, the work done by the electrostatic force. )

If the meta-charge is positive, and the charge put in it is negative, then the two charges attract each other, but if the negative charge is fixed, the positive charge will move to the negative charge faster, so w=e(positive)-e(negative) So: electric potential (positive)=w-e(negative) q (amount of charge of the elemental charge) electric potential (negative) = w-e(positive) q (amount of charge of negative charge) the former is positive and the latter is negative. (You can also look at it this way:.)

The direction of the electric field line points to the negative charge, and there is a certain reason: the electric potential is slowly decreasing along the direction of the electric field line, so the former is large and the latter is small, and it is difficult to judge the positive or negative. It is important to note that the electric potential is not affected by the Q value.

Suppose the electric field line is to the left and the charge is negative, then we can see the direction of the electric field line as the negative pole and the other end as the positive pole (the electric field line points from the positive pole to the negative pole, or from infinity to the negative pole, and the positive pole points to infinity!). (Got it).

The electrostatic force does work, that is, to see whether the "direction of electrostatic force" and the "direction of movement" of the charge are the same or opposite, and the same is the positive work, and the opposite is the negative work.

Of course, when the "electrostatic force direction" and the "moving direction" are at an acute angle, it is positive work, and when it is at an obtuse angle, it is negative work).

When the charge is not discharged, the "potential difference" between the two points in the electric field is determined. When the charge is released, the charge has "potential energy". The potential energy of the charge changes when it moves between two points.

- When the electrostatic force does positive work, the potential energy "decreases", and when it does negative work, the potential energy increases.

Definition of electric potential: =ep q

In the formula, the three quantities have "plus or minus", and the "plus and minus" signs should be substituted in the calculation.

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Problem description: Is it possible that only the balance of a charged object has electric potential energy in an electric field? Isn't it electrified?

I saw this sentence in the exercises: "The electric potential energy of a potassium chloride molecule is why a neutral molecule also has electric potential energy?" And why isn't it positive?

Analysis: Yes, only the charged body has empty potential energy in the electric field, and its calculation formula is e=q, where q is the amount of charge of the charged body, so the uncharged object has no electric potential energy.

Since potassium fluoride molecules are composed of positively charged protons and negatively charged electrons, the Coulomb force of the interaction of protons and electrons gives them electric potential energy.

The electric potential energy is relative, and its positive or negative depends on the choice of the zero potential point, so the potential energy of the charge can be positive or negative, which depends on the positive or negative of the q product.

The relationship between electric potential and electric potential energy, in the electric field, the ratio of the potential energy of a charge at a certain point to the amount of charge it carries, is called the electric potential of this point, which can also be called potential. Electric potential is a physical quantity that describes an electric field in terms of energy.

Electric potential energy, like gravitational potential energy, is a type of energy, and electric potential is another derived expression that denotes the nature of the electric field, not energy, and is more applicable because it is closer to life. The difference in electric potential energy is the work done by the electric field force, and the difference in electric potential is the voltage connection.

In an electric field, the ratio of the potential energy of a charge at a certain point to the amount of charge it carries is called the potential at this point.

The energy that a charge has in an electric field that is determined by its position due to the action of the electric field is called electric potential energy. The relationship between electric potential energy and zero potential surface is similar to the relationship between gravitational potential energy and zero potential surface (ground).

w=uq

First of all, the electric field is a conservative field.

You have to understand. It's the same as the gravity field of Ashisan. For a positive charge.

With. The electric field lines move in the direction. The electric potential energy decreases gradually. and a negative charge.

Quite the opposite. Because it has a symbol. You can understand it this way. Positive charge.

In an electric field, it will be subjected to.

The force is blocked in the direction of the electric field, so it will move in the direction of the electric field line. Then the energy of the electric field is converted into kinetic energy. Potential energy is naturally reduced. Negatively charged.

Opposite.. The direction of the electric field is given in the figure, as can be seen from the figure.

The velocity in the direction of the electric field is decreasing gradually. Because. The dotted line from A to B is gradual.

tends to be horizontal. Illustrate.

Particles are affected. The force in the direction of the inverting electric field. So it can only be a negative charge.

The electric potential energy is relative, a positive charge a, the closer to the positive charge O, the greater the potential energy of the positive charge a, that is, the electric potential is high and the potential energy is high; And the closer the negative charge b is to the positive charge O, the lower its potential energy is, that is, the electric potential is high and the potential energy is low.

In fact, as long as you remember one sentence, if you only receive the electric field force, move along the direction of the force, its potential energy must decrease, and move in the direction of the opposite force, the potential energy must increase.

The explanation of this problem is that the electric field line is emitted by a negative point charge, and you first assume that if the charged particle does not receive the electric field force, it will move in a straight line, because it will be deflected because it receives the downward electric field force, whether it is from a to b or b to a, it is a force in the opposite direction, so it is a negative charge.

I'm a junior in high school who just graduated, and I'm typing it word by word, begging for adoption.

First of all, the definition of electric field lines is clarified, starting from the positive charge to the negative charge, so the electric potential moving in the direction of the electric field line decreases. But the electric potential energy does not necessarily decrease, the electric potential energy is multiplied by the amount of electric charge, what if the charge is a negative charge... If it is negative, its potential energy will increase, why?

Because only a positive charge will move in the direction of the electric field line without an external force, while a negative charge must have an external force to do work on it if it wants to move in the direction of the electric field line, so its electric potential energy increases.

First of all, the force analysis of the dotted particle shows that the resultant force must be directed to the concave side (this is a law and can be used directly), and the component of this force in the direction of the electric field line must be opposite to the direction of the electric field line, so the charge is negatively charged.

The electric field force does negative work on it, and then from the analysis of the force at each point of the adaob motion, it can be seen that the electric field force and the direction of motion are greater than 90 degrees, so it does negative work.

First of all, the electric field is a conservative field, you see, just like the gravitational field. For a positive charge, it moves with the direction of the electric field lines. The electric potential energy decreases gradually.

Whereas the negative charge is the opposite. Because it has a symbol. You can understand it this way.

The positive charge in the electric field will experience a force along the direction of the electric field and hence will move in the direction of the electric field lines. Then the energy of the electric field is converted into kinetic energy. The potential energy naturally decreases.

Negative charge on the contrary.

The direction of the electric field is given, and it can be seen from the graph that the velocity along the direction of the electric field is decreasing. Because the dotted line from A to B is gradually leveling. Description The particle is subjected to a force in the direction of the inverting electric field. So it can only be a negative charge.

The answer is C.

Reason: It doesn't matter if the direction of movement is from A to B or B to A. From the diagram, we can know that the dynamic trajectory of the positive charge resembles an arc, which can be known by the knowledge of the centripetal force.

So the positive charge is subjected to a force to the right. Therefore, it is known that the direction of the electric field is to the left. From the knowledge of physics, it can be known that the electric potential decreases in the direction of the electric field line, so a > b.

First of all, it is known that the particle is positively charged and is only affected by the electric field force.

The particle always moves in the direction of the low electric potential, from point A to point B, so the electric potential A is greater than the electric potential B, and the field strength is to the right.

If I don't make it clear, please ask.

I think it is easier to judge from the curve motion conditions, making a tangent line on the trajectory is the direction of velocity, and the resultant force pointing to the concave side of the trajectory bend (to the right in this question) indicates that the electric field force is to the right, and the particle is positively charged, then the direction of the electric field is to the right and the electric potential a > b. This is the basic way to judge the motion of a curve.

If you don't understand, please ask.

The direction of the force is to the inside of the curve, so the direction of the electric field strength is to the right, and the TV will decrease along the direction of the field strength, so choose C

Because the electric field line is directed from the high potential point to the low electric potential point, and because the force direction of the negatively charged electron is opposite to the direction of the electric field line, the process of moving the electron from the high potential point to the low electric potential point is to overcome the electric field force to do work.

Regardless of whether it is a positive or negative charge, whenever work is done by overcoming the electric field force, the electric potential energy increases.

Because the direction of motion is opposite to the direction of the electric field force, the electric field force does negative work and the electric potential energy increases.

Electrons are negatively charged, and negative work is done along the electric field lines.