A question about electric potential, ask some questions about electric potential energy

We usually define the electric potential at infinity as zero, and this definition considers that there is only one charged body in space. When there is a connected charged body, it can be considered from the electric potential at a charged body, I think the questioner should know that f=k*q*q (r*r), so when starting from infinity, that is, the electric potential is zero, approaching a charged body, it can be seen from the formula, infinitely close to the charged body, the electric potential tends to infinity, and the conclusion is that the electric potential at the charged body is infinite.

So the electricity at each of the two equal amounts of dissimilar charges is positive infinity and negative infinity, respectively, so the electric potential at the midpoint is compromised to zero!

The electric potential decreases point by point along the direction of the electric field line, and the potential of the midpoint is smaller than that of the positive charge and larger than that of the negative charge, so it is considered to be 0

And the equipotential potential of the middle perpendicular line connected by the two charges is 0

Because the electric field caused by the point charge can be obtained by differentiation, the position of the point charge r, the potential is kq is the charge carried by the point charge. (There are positive and negative).

The principle of potential superposition is an algebraic operation.

So two equal amounts of heterogeneous charges connect to the midpoint, and the electric potential is zero.

Got it??

The field strength produced by an equal amount of dissimilar charge is perpendicular to the perpendicular line at the midpoint of the line.

Let the charge at infinity be zero.

Then it is not possible to move the charged particles from infinity to the midpoint of the line.

Because w=u*q

w=0q is not zero.

Then u=0

The 0 allele of the electric potential passes.

It can be derived from the formula for calculating the electric potential.

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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 correct understanding of electric potential is:

In the electric field, the ratio of the potential energy of a charge at a certain point to the amount of charge it carries (related to positive and negative, and the potential energy and the positive and negative of the charge can be judged by bringing in both the electric potential energy and the positive and negative of the charge in the calculation), which is called the electric potential of this point, which is usually expressed by .

Electric potential is a physical quantity that describes an electric field in terms of energy, and electric field strength describes the electric field in terms of force. The potential difference can generate an electric current in a closed circuit (when the potential difference is considerable, an insulator such as air can also become a conductor). The electric potential is also known as the potential.

The physical principle of electric potential:

The electric potential is only magnitude and has no direction and is a scalar quantity. Like topography, electric potential is also relative, and in specific applications, the potential energy of the standard position is often taken as zero, so the potential of the standard position is also zero. The electric potential is simply the result of a comparison with a standard position.

We often use the earth as our standard position.

In theoretical research, we often take infinity as the standard position, and in the habit, we often use the term "outside the electric field" instead of "zero electric potential position". The electric potential is a relative quantity, and its reference point can be arbitrarily chosen. Regardless of whether the selected object is charged or not, it can be selected as the zero reference point of the standard position.

For example, the earth itself is negatively charged, and its electric potential is about at infinity. Nonetheless, it is possible to use the Earth as a reference point for zero electric potential, and since the Earth itself is a large conductor, the capacitance is very large.

Therefore, adding or decreasing some charge on such a large conductor has little effect on its potential change. Its electric potential is relatively stable, so in general, the earth is still selected as the zero potential reference point.

The above content refers to Encyclopedia - Electric Potential.

Analysis: Solving with the principle of potential superposition and integration.

Place the rod horizontally on the x-axis, and make the perpendicular line at the midpoint of the rod as the y-axis.

At point p, where the distance from the perpendicular foot (coordinate origin) is a, the electric potential is.

2 kr) dq and half the length of the rod for the integration interval (symmetrical).

dq is the amount of charge taken on a small length of the rod and r is the distance from dq to point p.

Get 2 k root number (x 2 a 2) ]dx

2 k 1 root number (x 2 a 2) ]dx

2 k ln[ x root number (x 2 a 2)].

Substituting the integral interval of x from 0 to l 2 into the above equation, the potential of point p is .

2 k ln{[ l root number (l 2 4* a 2)] (2 a)}

Note: When the rod is positively charged, it is positive, then the p-point potential is positive. When the rod is negatively charged, it is negative, then the p-point potential is negative.

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.