Level 2 theorems in high school physics, Level 2 conclusions in high school physics

I advise you, don't memorize formulas, in fact, to be honest, there are so many second-order laws (formulas), you can memorize them! In the real exam room, it is guaranteed that you will be blindfolded, and there is often the kind of rote formula that will lead to the mistake of the whole question due to the misremembering of a symbol in the large exam, I still advise you to learn and use the basic formula, and repeatedly deduce the practice by yourself through the practice questions, do not blindly pursue speed, otherwise it will be too late to regret it, not for your points, just to see a problem like you, I would like to remind you, I have already gotten rid of the college entrance examination and worked! The college entrance examination is not easy for us, and I don't want you to go wrong!

I hope you forgive me for my own suggestions.

There are a lot, there are formulas, **, how to give it to you?

Such as: 5. Mechanical energy:

1 Ways to find mechanical work:

1) Use definitions to find constant force. (2) Work is sought from the effect of the work done (using the kinetic energy theorem or conservation of energy).

3) Seek merit from images. (4) Strive for work with average (when the force is linearly related to displacement).

5) Work is sought from power.

2 The work done by constant force has nothing to do with the path.

3 Functional relationship: frictional heat generation The kinetic energy lost by the system is equal to the total work of the sliding frictional force and the reaction force.

4 The work of the conservative force is equal to the negative value of the corresponding potential energy increment: .

5 The work of the action force and the work of the reaction force are not necessarily opposite in sign, and their total work is not necessarily zero.

6. The conveyor belt runs at a constant speed, and the small object is put on without muzzle velocity, and in the process of reaching the common velocity, the relative sliding distance is equal to the displacement of the small object, and the frictional heat generation is equal to the kinetic energy obtained by the small object.

7. Vibrations and Waves:

1. The object vibrates in simple harmonics, and the quantities that reach the maximum value in the equilibrium position are velocity, momentum, and kinetic energy.

The quantities that reach the maximum value at the maximum displacement are restoring force, acceleration, potential energy.

With the same displacement, velocity, recovery force, acceleration, kinetic energy, and potential energy at the same point, it is only possible to have different directions of motion.

After half a cycle, the object moves to a point of symmetry, with velocities equal in magnitude and opposite in direction.

The total work of the recovering force in half a period is zero, and the total impulse is.

After a cycle, the object moves back to its original position and all parameters are restored.

The total work of the recovering force in a cycle is zero and the total impulse is zero.

2. During the wave propagation, the particles of the medium are all forced to vibrate, and the vibration of the vibration source is repeated, but the starting time is different.

The wave source moves upwards first, and the transverse wave crest is in front; The source of the wave moves downward first, and the resulting transverse wave trough comes first.

The way the wave propagates: the front-end waveform does not change, translates forward and extends.

3 When discussing the propagation distance, time, period, and speed of a wave from the image of a wave: pay attention to "bidirectional" and "multiple solutions".

4 On the waveform diagram, the direction of motion of the medium particles: "uphill downhill, downhill up".

5 When a wave enters another medium, the frequency does not change, the wavelength and the speed of the wave change, and the wavelength is proportional to the speed of the wave.

6 When a wave interferes, the movement of the wave is not seen. The positions of the vibration strengthening point and the vibration weakening point remain unchanged and are separated from each other.

The "second-level theorem" is an inference derived from the basic laws and basic formulas in some common physical situations, also known as "semi-finished products".Because these scenarios and these inferences occur frequently or are complicated to derive when doing questions, it is important to memorize these "second-level conclusions" and use them directly when doing fill-in-the-blank or multiple-choice questions. Although you have to do the equation step by step, you can't directly quote the "Qingze Level 2 Conclusion", but as long as you remember the "Level 2 Conclusion", you can predict the result, which can simplify the calculation and improve the starting point of thinking, which is also useful.

Newton's gravitational pull.

Cavendish used a torsion scale experiment to determine the gravitational constant g

Fresnel: Refractive reflection law, Poisson bright spot.

Michelson Exact value of the speed of light.

Thomas Young used interferometry to measure the wavelength of light waves.

Coulomb Coulomb's law.

Amps discover the interaction forces between electric currents.

Faraday electromagnetic induction.

Planck quantum theory.

De Broglie, Matter Waves.

Maxwell Theory of Electromagnetic Fields.

Hertz discovers electromagnetic waves.

Thomson discovered electrons.

Chadwick discovered the neutron.

Roentgen X-ray.

Rutherford: Protons were discovered by particle scattering experiments.

Albert Einstein's relativistic photoelectric effect mass-energy equation.

Joliot, Curie and his wife rays.

Brown Brownian motion.

Oster wires are energized to produce a magnetic effect.

Hooke's Law.