About the question of high school physics hot blood, thank you!

To solve this kind of similar physics problem, it is generally necessary to start from the definition, the average kinetic energy of all molecules in physics is the average kinetic energy of the thermal motion of molecules; As the temperature of the object increases, the thermal motion of the molecules intensifies, and the average kinetic energy of the thermal motion of the molecule also increases, and the higher the temperature, the greater the average kinetic energy of the thermal motion of the molecule. It can be seen that the average kinetic energy of the thermal motion of molecules is determined by the physical temperature, so the average kinetic energy of different objects with the same temperature can be the same.

As for the friction force increasing the internal energy of the object, that is, the average kinetic energy of the thermal motion of the object has increased, and the frictional force does work on the object, the physical problem will increase, so that the average kinetic energy of the molecular thermal motion of the object also increases, and the internal energy increases! (The second question does not mention volume, so it is not considered) Another relational quantity of internal energy is molecular potential energy, which is related to volume, and temperature and volume should be taken into account when considering internal energy. When studying physics, conceptual things should not only be memorized, but also understood and memorized.

1.Yes, temperature is a measure of the average kinetic energy of a molecule.

2.Does it mean that frictional energy increases the potential energy of the molecule: Not true.

Friction is the work done by an external force on the system to increase the internal energy and increase the average kinetic energy.

1 Yes, temperature is a measure of the average kinetic energy of a molecule.

2, Work done and heat transfer can change the internal energy of an object which is macroscopic.

Whereas, internal energy is the sum of the potential energy of the molecule and the kinetic energy of the molecule which is microscopic.

Why do you have to pull these two together!

Friction is to do work, and doing work is a way to change the internal energy, don't divide the internal energy again.

1.Yes, temperature is a measure of the average kinetic energy of a molecule, and it is also applicable to different substances.

2.Friction generates heat, which increases the temperature and increases the average kinetic energy of the molecules, thus increasing the internal energy of the object.

The decomposition of the force ......That's just the basics.

Systematic error is also known as regular error. It is that under certain measurement conditions, when the same measured size is repeatedly measured many times, the magnitude and sign of the error value (positive or negative value) remain unchanged; Or when the conditions change, the error that changes according to a certain law.

In the measurement, even if the factors that cause systematic error are excluded (in fact, it is impossible and unnecessary to be absolutely excluded), and careful observation is carried out, there will still be a certain error, and this kind of irregular change (fluctuation) of each measured value caused by accidental or uncertain factors is called accidental error, or random error.

It's a fortuitous error!

This is caused by an error and is not an error.

It's not an error, it's an operational error.

The difference between error and error is that error cannot be avoided, error can be avoided, and when discussing error, it is under the condition that the method and instrument have been selected, if the condition or method is changed, it is another experiment

If the acceleration is uniform first, and then the deceleration is uniform, then the maximum velocity v is (4+6)x2 10 =2m s, and 2 a1 x=v2 0

2 a2 x=0－v2

Substituting the data, the average velocity in 210s is (4+6) 10=1m s

(1) mv 2 r=bqv centripetal force is provided by the Lorentz force, v=bqr m t=2%r v % means pi t=2%m bq The alternating current period should be the same as the circular motion period in order to play an accelerating role: f=1 t ......

2）v=bqr/m ……

The gravitational force of the car g = 15000N, and its centripetal force is all provided by gravity. When the required centripetal force is greater than gravity, the car will take off.

F direction = mv2 r 15000, the solution is v 8000m s

So its speed is not less than 8000m s

First, analyze the problem scenario and think about whether the question asks you again: when the earth is moving in a circle, when v is equal to what, the centrifugal force is equal to gravity.

Knowing the above, it is easy to say: according to the formula f=mv square r, where f=mg is converted to v square = gr (g and r are known, v can be calculated).

It can be seen that V has nothing to do with the quality of the car.

ps:r 6400km should be converted to 6400000m

From the problem, we can see that gravity g provides centripetal force and f direction = g=mv2 r to get v=8000m s, so the minimum velocity is 8000m s

Color streaks appear on the water surface of the oil film, because after the oil film is irradiated by light, part of the upper surface of the light film is reflected, and part of the transmission is reflected by the lower surface of the oil film.

The reflected light on the upper and lower surfaces of the oil film will interact with each other, eventually forming streaks;

This phenomenon in optics is called interference of light, not dispersion;

The dispersion of light refers to the separation of various colors of light after white light enters the medium;

But the thickness of the oil film here is very small, and the dispersion effect is negligible.

Isn't that right... The answer is very wrong ... Don't subvert my worldview ... I suggest asking the teacher tomorrow. If it's wrong teach me ...

The phenomenon of dispersion of light.

Thin-film interference.

The color pattern is because of the phenomenon of interference.