What is the main topic of physics in the second year of junior high school, and what is the main top

The main content of physics in the second year of junior high school is: optics, electricity, acoustics and other basic and extensive points, among which the principle of "convex lens" in optics and circuit analysis in electricity, the relationship between various electrical instruments will be more complicated, be sure to listen carefully!

From the perspective of my sophomore physics major, electricity is the most important, and other points such as acoustics can be memorized without too much effort.

Good luck with your studies!

Mainly electrical.

What Ohm's law, voltammetry, Joule's law, Oersted experiment, etc.

The second is the phenomenon of light and sound (the first semester of the second year of junior high school).

It's easier to think about the semester.

But it must not be perfunctory.

The second semester of the second year of junior high school is a bit difficult.

If the foundation is not laid.

You just wait to fail!!

Acoustics (how an object makes sound, frequency units, calculations).

Optics (optical path diagram, reflection, refraction, concave and convex lens, face mirror, speed of light) Electricity (current, voltage, resistance, electric power, electricity and heat, electricity and magnetism) I am from Shenyang, the textbook may be different from other places, we here electricity is basically learned in the next semester, and the last semester to learn sound, light, electricity, gone.

Voltage, resistance, Ohm's law, electrical power, electricity and magnetism, transmission of information, even the second year of the first two*

Most of the talk is about forces, buoyancy and molecules and atoms.

leverage, etc.

There are a lot of calculations, and the key is to learn the concepts clearly, memorize them, and you can get a good score.

It's simple, and it's no different from math at first.

The last semester was very simple, you have to listen carefully during class, and a score of 98 is no problem!

The next semester will be more difficult, in addition to listening carefully, you also have to do more exercises!

I usually ...... 95 points

I suggest you go on.

Take a look at the physics e-textbook for the second year of junior high school.

Is it a human-taught version? Each version is different

Chapter 1 Opening the Door to the Physical World.

Section 1 Into the Magic.

Section 2 The Road of Exploration.

Section 3 Stand on the shoulders of giants.

I don't think this chapter is very important, our teacher said that it is enough to memorize the 7 methods on 13 pages: communication and cooperation, asking questions, conjectures and hypotheses, making plans and designing experiments, conducting experiments and collecting evidence, analyzing and demonstrating, and evaluating).

Chapter 2 The World of Movement.

Section 1 Movement and Stillness.

Section 2 Measurement of Length and Time.

Section 3 Fast and Slow.

Section 4 Science**: Changes in Speed.

Well, this chapter. When talking about 'force', it is a bit important to remember the formula v=s t in the mid-term).

Chapter 3: The World of Sound.

Section 1 Science**: The Production and Propagation of Sound.

Section 2 Music and Noise.

Section 3 Ultrasound and Infrasound.

This chapter is very important! The teacher said that this chapter can not lose points, you must remember Oh and the end of the note, put forward a few key points: 1. The speed of air transmission:

340m s 2, auditory effect and sound strength 3, loudness, pitch and timbre are the three factors that determine the characteristics of musical sounds).

Chapter 4: Colorful Light.

Section 1 Propagation of Light.

Section 2 Reflection of light.

Section 3 Refraction of light.

The midterm exam is only here, and this chapter is also very important to remember that the solar eclipse and the lunar eclipse may have to be tested, and the particularly important one is easy to confuse with sound, sound cannot propagate in a vacuum, and the propagation speed of air liquid solid and light can propagate in a vacuum, and the propagation speed of vacuum air liquid solid (transparent) light propagation speed is 3 10 to the power of air propagation is a little slower than vacuum Its propagation speed is also seen as 3 10 power The propagation velocity in shiu is about 3 4 of the vacuum, The propagation velocity in glass is about 2 3 of a vacuum).

The main learning content can be divided into five parts: acoustics, optics, thermal, electrical, and mechanics.

1. The generation and propagation of sound, the characteristics of sound;

2. Linear propagation of light, reflection of light, refraction of light, invisible light, lens imaging;

3. Internal energy, change of internal energy, heat calculation, utilization of internal energy, internal combustion engine, electromagnetism;

4. The series and parallel connection of resistors, Ohm's law of some circuits, and the current and voltage are learned;

5. The movement of objects, force, force and motion, bush pressure and pressure, buoyancy, simple machinery, work and infiltration and sales.

The human education version is as follows (I don't know what version you want):

Volume I: Chapter 1 Acoustic Phenomena.

1. Sound generation and propagation.

2. How do we hear sounds?

3. Characteristics of sound.

Fourth, the harm and control of noise.

5. The use of sound.

Chapter 2 The Phenomenon of Light.

1. The propagation of light.

2. Reflection of light.

3. Plane mirror imaging.

Fourth, the refraction of light.

5. Dispersion of light.

6. Invisible light.

Chapter 3 Lenses and Their Applications.

1. Lens. Second, the lens of life.

3. The law of convex lens imaging.

4. Eyes and glasses.

5. Microscopes and telescopes.

Chapter 4 Changes in the state of matter.

1. Thermometer.

2. Melting and solidification.

3. Vaporization and liquefaction.

Fourth, sublimation and condensation.

Chapter 5 Currents and Circuits.

1. Charge. 2. Current and circuit.

3. Series and parallel.

Fourth, the strength of the current.

5. The law of current in series and parallel circuits.

Volume II: Chapter 6 Voltage and Resistance.

1. Voltage. Second, the law of series and parallel circuit voltage.

3. Resistance. Fourth, the rheostat.

Chapter 7: Ohm's Law.

1. The relationship between the current on the resistor and the voltage at both ends.

2. Ohm's law and its application.

3. Measure the resistance of the small bulb.

Fourth, Ohm's law and safe use of electricity.

Chapter 8 Electrical Power.

1. Electrical energy. 2. Electrical power.

3. Measure the electrical power of the small bulb.

4. Electricity and heat.

5. Electricity power and safe electricity consumption.

Sixth, the common sense of electricity in life.

Chapter 9 Electricity and Magnetism.

1. Magnetic phenomena.

2. Magnetic field. 3. Electromagnetism.

Fourth, electromagnets.

5. Electromagnetic relay speaker.

6. Electric motor.

7. Magnetism generates electricity.

Chapter 10 Transmission of Information.

First, modern tailwind ears **.

Second, the ocean of electromagnetic waves.

Radio, television and mobile communications.

Fourth, the road of information is getting wider and wider.

In the time of seconds, the sound is propagating, and the car is also moving forward in the time of the second, and the distance traveled by the sound is equal to 440m which is twice as long as it is minus the distance traveled by the car in seconds. So let's set the speed of the car to be x meters and seconds and 440 meters and seconds.

Eighth-grade physics is generally divided into two volumes, and there may be a small difference in the layout of the content published by various publishers.

If it is the first volume of the people's education edition, the proportion of sound, light, thermoelectric and electric light is relatively large, and the second volume of voltage resistance, Ohm's law, electrical power, magnetic phenomena, the transmission of information, and electrical power are more difficult to focus on.

Well, you just check it on the Internet, the physics of the second year of junior high school last semester is very simple, and it can scatter your simple soul, but then you have to study hard, learn well, and strive to get 100 points in every exam, hey I will go to the third year of junior high school at the beginning of school, and the second year of junior high school is the core of junior high school, the key, very important, more important than your life (in my opinion), to cherish

Electricity, whatever. It's hard. You can start by looking up the 8th grade e-textbook on the Internet. Let's preview it first!

Sound and light, the second year of junior high school is basically electricity, learn hard, it's very simple.

The most basic, light and electricity bar. It's been years since I graduated...