Velocity. Science Topics. High score of 50

Problem: Yes, (l), (3) In the phenomenon, due to the uneven density of the air, the light is refracted and shines into the stars blinking, the person swaying, and the opposite thing swaying.

Question 2: No, there is no air on the moon.

Problem 3: It can avoid the inconvenience caused by atmospheric refraction to observation.

Similar to star wink. It's all because of the change in the air.

There is no blinking on the moon. Because there is no atmosphere.

There will be no atmospheric interference in the sky.

Xiao Ming likes to watch the stars and listen to his grandmother tell the story of the Cowherd and the Weaver Girl. One night, Xiao Ming suddenly thought: Why do the stars keep blinking?

Can they glow one moment and not at all? No way! So why?

In order to study this problem, Xiao Ming collected the following light phenomena, from which the cause may be found.

1) There is a bonfire outside the field to barbecue, and you can see people on the ground shaking through the campfire.

2) In front of the haha mirror, you will see yourself getting bigger.

3) In summer, you can see that there seems to be a wave of water vapor rising on the asphalt road, and you can see things shaking on the other side through the water vapor.

Question:1Do you think any of these phenomena collected by Xiao Ming are similar to the research question of star blinking? If so, do you think they are similar?

2.Do you now know why the stars blink? Imagine if you see a star on the moon blinking?

3) The astronomical telescope in the United States was sent to the sky by scientists with a lot of effort, and it is very expensive to manufacture and maintain. Why did scientists send astronomical telescopes to the sky, and what are the benefits of doing so?

It's too hard to give 1000 points.

1 a cu（oh）2co3

h cu（oh）2

2 Write out the chemical equation for the g l m conversion.

Fe +2HCl = FeCl2 +H2 (sulfuric acid H2SO4 is OK)3 b The elements that must be contained in a substance are the elements Fe and O that must be contained (conservation of mass can be explained).

4 In moist air, a can be generated on the surface, and the chemical equation for its change can be written.

cu + o2 + co2 +h2o =cu（oh）2co3

When doing low-pressure breathing exercises, the mass pressed on him is between 65 8-65, that is, between.

The mass does not change with the environment, so his weight is still 65kg when he does the weightless space training

You're in your first year of junior high school

Solution: When doing low-pressure breathing training: equivalent to 65kg*8=520kg weight pressed on the body, if he is weightless, his mass is 65kg!

1: An object equivalent to (65kg*8=520kg—65kg*) is pressed on him. 2: Since the mass of people from the earth to the moon is unchanged, Yang Liwei's weight is still about 65kg.

I think it's mainly your mentality, and I'm also in junior high school. I know your mood very well right now, and to tell you the truth, I'm also very nervous. I couldn't grasp the direction of revision, and my most proud subject, the Chinese language, also dropped a lot.

When I was reading, I was always nervous and couldn't calm down, and as a result, I couldn't feel the feelings of the article. And mathematics is the most outrageous, this time the second model actually missed all the application problems and didn't think about it. In retrospect, as long as I calmed down, like I did last semester.

I'm more than capable of doing them well because they're super easy compared to what I usually do. Therefore, adjust your mentality, build self-confidence, and believe that you can do it. （ps：

There is also a small suggestion, if the state is so unstable, it is recommended that you think twice when you apply for the exam, because the high school entrance examination is different from the college entrance examination, and it will be difficult to recover if you miss one. ）

v gasoline = m p = 1000kg 800kg cubic meter = cubic meter = 1250 liters 290 1250 = yuan is about equal to yuan Is this right?

1. The device at the B division plays the role of a control experiment.

2. Light, temperature, oxygen, moisture, trace elements.

Question 1. bQuestion 2. Illumination time. Ambient temperature. Trace element.

The stratosphere is above the troposphere.

In the mid-latitudes, the stratosphere is located at an altitude of 10 km to 50 km above the surface, while in the polar regions, it begins at an altitude of about 8 km above the surface. The stratosphere is sandwiched between the troposphere and the mesosphere.

(Troposphere): about 8 17 km upwards from the surface, varying altitudes, with increasing (decreasing) temperatures.

Stratosphere): Above the troposphere to (50) km, the temperature increases with altitude.

Mesosphere): 55 (85) km, temperature increases (decreases) with altitude.

Ionosphere): 85 (500) km, temperature increases with altitude (increases).

Outer layer) :(500) km, the temperature increases with altitude (increases). But beyond (1000) km, the density of the atmosphere has become very small, approaching (vacuum) at 5000 km.

The phenomenon of vaporization can only be carried out at a certain temperature.

Footage seen on a classroom projector.