Can anyone help me summarize the knowledge of Physics Elective 3 1 Electrostatic Field?

There is no hurry. In this chapter, just read the sample questions in the book.

Chapter 1 Electrostatic Fields Formula Set.

1. The minimum amount of charge is called "meta-charge" e= The amount of charge carried by an electron is 1e

2. Coulomb's law f = kqq r2 k: electrostatic force constant q: source charge q: tentative charge.

3. Electric field strength (vector).

e = f q = kq r2 e in the same direction as the electrostatic force experienced by the positive charge at that point.

4. Electric field lines.

1) The tangent direction of each point on the electric field line indicates the direction of the field strength of the point.

2) The electric field lines do not intersect.

3) The density of the electric field lines or the small and large spacing of the equipotential surface indicate the weakness and strength of the field strength.

4) The electric field lines of the uniform electric field are parallel lines with equal intervals.

5) The electric field line points to the direction of the electric potential decrease, that is, from the equipotential surface with high electric potential to the equipotential surface with low electric potential.

5. The work done by the electrostatic force is equal to the reduction of electric potential energy.

WAB = EPA - EPB = Q e DAB = Q UAB DAB: AB The distance between two points along the direction of the electric field.

The electric potential energy of a charge at a point is equal to the work done by the electrostatic force when it moves it from that point to the position of zero potential energy.

6. Electric potential (scalar).

The ratio of the potential energy of an ep q charge at a point in the electric field to the amount of its charge is called the potential at this point.

There is no necessary relationship between the magnitude of the electric potential and the magnitude of the field strength.

Electric Field Lines: Some hypothetical curves introduced to describe the distribution of electric field intensity.

Properties: Closed curves that start from a positive charge and end with a negative charge.

The denseness of the electric field line represents the strength of the field, and the denser the field strength, the larger the field strength, and the smaller the field strength.

The tangent direction of a point on the electric field line is the direction of the field strength of that point.

Electric field lines cannot intersect and bend (because there will be two directions when they intersect) Students, you must remember several common electric field line distribution diagrams and send the diagram to yourself. If it's not common, I won't test you, but if you want to take the test, you will also test some common sense, and remember the properties that you summarized earlier.

Electric Field Lines: Electric field lines start with a positive charge and end at a negative charge, or at infinity, or start at a negative charge, or start at a positive charge and end at infinity. Not closed. The direction of the field strength is the same as the electric field line along the cut open line of the electric field line, and it is the same if it is a straight electric field line.

The electric field lines start at the positive charge and end at the negative charge or start at infinity or start at infinity or start at the positive charge and end at infinity. (The basic phase chain is equivalent to the transfer of a positive charge to a negative charge).

The denser the electric field lines, the stronger the field strength.

9. Electric field.

There are two types of electric charges in nature: positive and negative.

2) Law of Conservation of Charge:

2.Coulomb's law.

Inversely proportional, the direction of the force is on their line.

2) Formula: 3) Applicable conditions: point charge in vacuum.

Point charge is an idealized model. If the linearity of the charged body itself is much smaller than the distance between the interacting charged bodies, so that the volume and shape of the charged body have a negligible effect on the interacting force, such a charged body can be regarded as a point charge, but the point charge itself is not necessarily small, and the amount of charge carried is not necessarily very small.

3.Electric field strength, electric field lines.

1) Electric field: 2) Electric field strength:

3) Electric Field Lines:

4) Uniform electric field:

5) Superposition of electric field strengths:

4.Potential difference u:

5.Electric potential :

2) Along the direction of the electric field lines, the electric potential is getting lower and lower.

6.Electric potential energy: The electric potential energy of a charge at a point in the electric field is numerically equal to the work done by the electric field force to move the charge from that point to where the electric potential energy is zero (where the electric potential is zero).

qu7.Equipotential Surface: A surface formed by points with equal electric potential in an electric field is called an equipotential surface.

1) The electric potential of each point on the equipotential surface is equal, and the electric field force of the moving charge on the equipotential surface does not do work.

2) The equipotential surface must be perpendicular to the electric field lines, and the electric field lines are always directed from the higher potential surface to the lower potential surface.

3) When drawing equipotential surfaces (lines), the potential difference between two adjacent equipotential surfaces (or lines) is generally equal. In this way, the field is strong at the dense place of the equipotential surface (line), and the field strength is small at the sparse place of the equipotential surface (line).

8.Functional relationships in electric fields.

1) The work done by the electric field force is not related to the path, but only to the initial and final positions.

It can be calculated by the formula w=qecos (which is only suitable for uniform electric fields) or by the kinetic energy theorem.

2) Only the electric field force does the work, and the sum of the kinetic energy of the electric potential energy and the charge remains the same.

3) Only the electric field force and gravity do the work, and the sum of electric potential energy, gravitational potential energy, and kinetic energy remains unchanged.

9.Electrostatic shielding: The field strength of the cavity part of the cavity conductor or metal mesh cover in the electric field is zero everywhere, that is, it can cover the external electric field and make the inside not affected by the external electric field, which is electrostatic shielding.

10.The motion of charged particles in an electric field.

1) Charged particles accelerate in an electric field.

2) Deflection of charged particles in an electric field.

3) Whether or not to consider the gravity of charged particles depends on the specific situation. Generally speaking:

Elementary particles, such as electrons, protons, particles, ions, etc., generally do not consider gravity (but mass cannot be ignored) unless they are stated or explicitly implied

Charged particles, such as liquid droplets, oil droplets, dust, small balls, etc., generally cannot ignore gravity unless there is an explanation or explicit implication.

4) Charged particles move in a composite field of uniform electric field and gravitational field.

Since the electric field force and gravity of charged particles in a uniform electric field are constant forces, they can be dealt with in two ways: orthogonal decomposition method; Equivalent "gravity" method.

12.Capacitance.

10. Stable current.

1.Definition of current ---1):

2) Direction of current:

2.Current Intensity:

High School Physics Elective 3-1 Formula.

Commonly used formulas in electromagnetism.

Electric field strength: e=f q

Point charge electric field strength: e=kq r

Uniform electric field: e=u d

Electric potential energy: e

q Potential difference: u

Work done by electrostatic force: w = qu

Capacitance definition: c=q u

Capacitance: c = s 4 kd

The motion of charged particles in a uniform electric field.

Acceleration uniform electric field: 1 2*mv quv

2 qu m deflection uniform electric field:

Vertical acceleration: a=qu md

Vertical displacement: y=1 2*at

1/2*(qu/md)*(x/v₀)²

Deflection angle: =v v =qux md(v).

Coulomb's law.

f is equal to (k times q1

q2) Divide r to the 2nd power.

f for between them.

The amount of electricity carried by the electrostatic force Q1Q2 charge.

k is the electrostatic constant and r is the distance.

The answer is as follows, ask for .........

1 Positive and negative repulsion attraction Amount of charge The end of the conductor close to the charged body has a different charge, and the end away from the charged body has a charge of the same number Inductive transfer transfer.

2 equals e equals an integer multiple of e.

3 Point Charge The product of the amount of charge The square of the distance on the line between the point charges.

4 has an electrostatic force in an electric field.

5 The ratio of the force to which the tentative charge is subjected to its amount f q v m or n c is in the same direction and the electrostatic force is in the opposite direction.

6 kq r 2 vector sum.

7 Direction of electric field intensity.

8 Positive and negative intersection overlap size.

9 size orientation.

10 displacement of the distance traveled by the electric potential energy.

11 Positive Decrease Negative Increase The amount of change in electric potential energy w=qelcos

12 The pre-selected potential energy zero point at infinity.

13 The ratio of the electric potential energy to the amount of electric charge = ep q decreases the zero electric potential point at infinity.

14 The amount of work done by the electrostatic force charge u=w q volts v

15 Test the charge.

16 The electric potential is equal.

17 vertical vertical high low do not do.

18 The product of the magnitude of the electric field strength and the distance between two points along the direction of the electric field strength ed u d The electric potential decreasing per unit distance along the direction of the electric field.

19 v/m n/c

20 insulated from each other are very close to each other.

21 The two plates are charged and stored in the absolute value of the amount of charge carried by one plate.

22 The ratio of the amount of charge carried to the potential difference between the two plates c=q u The nature of the capacitor itself.

23 Charged Capacitor The ratio of the amount of charge carried to the potential difference between the two plates.

24 Fara, F 10, 12

25 The area of the two poles of the capacitor The dielectric coefficient of the medium between the plates ( ) The distance between the two plates.

26 Fixed Capacitors Variable capacitors.

27 Limit voltage Normal.

28 Uniform (decreasing) velocity straight line Uniform strength The initial kinetic energy generated by the point charge is zero 2 qu m The initial kinetic energy is not zero v0+ 2 qu m

29 Vertical Uniform velocity curve Horizontal throwing motion Orthogonal decomposition method Uniform velocity motion l v0 Linear motion with uniform variable velocity with zero initial velocity.

qu/md qul^2 /2mdv0^2 qul/mdv0^2

Solution: 1,. The electric potential at the two points ab is the same, and the electric field force does not do work during the process of the block from a to b.

From the kinetic energy theorem: -fl 2=0-e0 (the coefficient of kinetic friction is not easy to beat, you should be able to find it).

Apply the kinetic energy theorem to b:

fl 4+qu=0-ne0 (f has been found above, just substitute) 3Because it finally stops at point O, the work done by the electric field force is only related to the position of the beginning and the end, and the work done by frictional force is related to the distance.

Kinetic energy theorem: -qu-fs=0-e0 (U here is the same as above, but u(ao)=-u(ob), you know, hehe).

I'm tired.,There's no formula.,It's not good to type.,I don't understand and ask again.。