What are the knowledge points and formulas of physics elective 3-1 in the new curriculum standard?

What are the knowledge points and formulas of physics elective 3-1 in the new curriculum standard?

Chapter one: electrostatic field
Section 1 Law of conservation of charge
Coulomb's law
3 electric field strength
Potential energy and potential
5 potential difference
The relationship between potential difference and electric field intensity
7 Application of electrostatic phenomena
8 capacitance of capacitor
Application of 9 charged particles in electric field
Chapter 2: constant current
Section 1 power supply and current
2 electromotive force
Three Ohm's law
4 series circuit and parallel circuit
5 Joule's law
6 law of resistance
Ohm's law of closed circuit
8 multi purpose meter
9 experiment: measure the electromotive force and internal resistance of the battery
Simple logic circuit
Chapter 3: magnetic field
Section 1 magnetic phenomena and magnetic fields
2 magnetic induction
Three kinds of common magnetic fields
4. Force of magnetic field on electrified wire
The force of magnetic field on moving charge
Motion of charged particles in uniform magnetic field
There are too many formulas. It's useless if I don't understand them. I won't write them

Summary of 3-1 knowledge points of physics elective course,

There are two kinds of charges in nature: positive and negative. (2) law of charge conservation: 2. Coulomb's law is inversely proportional, and the direction of the force is on their line. (2) formula: (3) applicable conditions: point charge in vacuum. Point charge is an idealized model

Summary of knowledge points of physics elective 3-1

Electric field 1. Two kinds of electric charges --- (1) there are two kinds of electric charges in nature: positive charge and negative charge. (2) law of charge conservation: 2. Coulomb's Law (1) content: in vacuum, the force between two point charges is directly proportional to the product of their charge quantity and inversely proportional to the square of the distance between them

As for the physical meaning of the formula r = u / I, the correct one in the following statement is (d)
The resistance of a conductor is directly proportional to the voltage at both ends of it and inversely proportional to the current passing through it
B. the greater the current passing through the conductor, the lower the resistance
C. The greater the voltage applied to both ends of the conductor, the greater the resistance
The resistance of a conductor is equal to the ratio of the voltage at both ends of the conductor to the current passing through it
This is for sure. The teacher said that there are two points to consider in this problem: 1. Determinate and definable
2. The quantity determined by the ratio
Still did not understand very thoroughly. Help to explain
When the voltage at both ends of a resistance is zero, the resistance is not zero. Therefore, it cannot be said that "resistance is directly proportional to voltage and inversely proportional to current"

There are three quantities in the formula, right? That is to say, it is impossible for any two quantities to avoid the third quantity for comparison alone. The mistake is that the resistance will not change with cigarette lighting and current. Because resistance is the property of conductor itself, r = u / I is the calculation formula of conductor resistance, that is to say, the resistance of a section of conductor is constant. We just use the formula

For a certain section of conductor, the physical meaning of the formula r = u / I is
The resistance of a conductor is directly proportional to the voltage at both ends of the conductor; the resistance of B conductor is inversely proportional to the current passing through the conductor; the resistance of C conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the current passing through the conductor; the resistance of D conductor is equal to the ratio of the voltage at both ends of the conductor to the current passing through the conductor Which one should you choose? And please tell us the analysis process or reasons of the four options. If you don't know how, don't choose the answers indiscriminately

Choose D
A. The resistance of a conductor is the property of the conductor, which is related to the nature of the conductor itself and has nothing to do with the voltage at both ends of the conductor
B. Same as above
C. Ohm's law says that the current passing through a conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor. This sentence means that the current changes with the change of voltage and resistance, not the resistance
D. According to Ohm's law

In the physical formula, = u / R. where R is 22 Ω and I is 5 (a), then u = ()

110 (V)

Physical electricity formula P = uit, but t time is unknown?
1. A consumer marked as "220v44w" is connected to the 110V circuit, and the actual power is_____ (let its resistance be constant)

Because w = UI, I = u / R
So w = (U * U) / R, r = (U * U) / W
R = (220 V * 220 V) / 44 w = 1100 Ω
W actual = (110V * 110V) / 1100 Ω = 11W

Thermal effect of current: if q = I ^ 2rt, because u = RI, then q = uit, because UI = u ^ 2 / R, then q = u ^ 2 / R × T. when the first formula I and T are constant, R increases,
Q increases. In the second formula, when u and T are constant, R increases but Q decreases. Why?

In the first formula, you assume that R becomes larger and Q becomes larger when u is constant, but I decreases when R becomes larger, so the conclusion of one is wrong. In the second formula, u is constant and R increases, so Q decreases. At this time, I also decreases. It is also true in the first formula!

What is the formula of S = N.H in physics? Explain what is s, what is n, what is h

S = NH is the calculation formula of moving pulley or pulley block in physics. N represents the number of segments of the rope pulling the pulley and the weight in the pulley block, H represents the height of the weight rising, and s represents the rising distance of the free end of the rope

In physics, there is such a formula that P = the square of u divided by R. if we know P and R, we can find U

o(∩_ ∩) O & nbsp; & nbsp; hope to adopt