Ask a few scientific questions urgently, and it must be right

Round and solid It is directly formed by the convergence of light and can be presented upside down on the screen, so it is a real image.

It won't be observed, it will change.

sos 1.When it shines on a "green" object, the object absorbs the other six colors in the white light, and then reflects the green back to be captured by the human eye, which is called the green color of the object. When you put a green object inside the red light, the red is absorbed, and there is no green reflected back, our eyes don't feel any light, so we think the object is black.

2.References for small-hole imaging.

3.The light spots left on the ground by the sunlight passing through the dense woods are (round) shaped, but in fact it is a shrunken image of the sun through the small holes between the leaves"Real"or"Virtual"Like, your judgment is based on the principle of small hole imaging

4.The shape of the hole will not be filled"Yes"or"No, it won't") affects the shape of the image.

5.Have you ever observed the color of colored objects in different light? Whether its color will change.

The color of colored objects will change under other colors, for example, people look like they are green under the illumination of green light. It can be judged by the three primary colors of light.

Categories: Education Academic Exams >> Study Help.

Problem description: Is it true or false that water can dissolve some solids, but not some gases and liquids? After the rock sugar is dissolved in water, the rock sugar does not exist, right or wrong? Put some lard in the hot vegetable soup, and the lard will dissolve, is this also a dissolution phenomenon, right or wrong?

When the water evaporates, the substance dissolved in the water disappears, right or wrong? Is it true that anything that cannot be dissolved in water will sink to the bottom of the water when it is put into water? After stopping the gong, you can still hear the sound of the gong, is the gong surface vibrating right or wrong?

Is it right or wrong that steel travels faster than air? Is it true or wrong that sound cannot travel in water? Sound can only travel in one direction, right or wrong?

Please judge the wrong right or wrong according to the order of the questions, and it is better to write why, I thank you in advance!

Analysis: 1) Water can dissolve some gases, such as carbonic acid solution, and the "dissolution" of water to the solution is called dilution.

2) When rock sugar is dissolved in water, the rock sugar solids will disappear, but it will still exist in molecular form.

3) The lard is dissolved, and it is the lard that is dissolved by heat.

4) Crystals may precipitate and gases may disappear.

5) No, wood will float, and whether it will float depends on its density.

6) Yes, it could also be an aftersound.

7) Yes, iron is denser than air.

8) No, sound propagation requires a medium, which can travel in water.

9) Sound waves travel in all directions in the air.

Antennae, shell, mouth, body, will leave mucus on the ground, pests, 1 touch, 2 vision, 3 senses, 4, smell... Stress, turtles and screws, etc.

Explained with the theory of relativity.

Grandpa said that running 2km is relative to the treadmill.

The reference he chose was the treadmill, and Xiao Ming's statement was relative to the surrounding environment (floor, walls, ceiling, etc.).

The reference material chosen is the floor, wall, ceiling, etc.

Motion is absolute, rest is relative, there is no such thing as absolute rest!!

1. Some people who "pretend to be ghosts" have such a "unique skill": they pull out the "ghosts" from the boiling oil pot with their hands, but their hands are unharmed. The secret lies in the "oil" in the pot; The upper layer is real vegetable oil (boiling point is about 300), while the lower layer is other liquids, and the boiling point of this liquid is most likely ——(

Left and right, left and right, left and right2, on a summer night, a unique gathering of "insects" should be held in the forest to study how to adapt more to the increasingly harsh environment. Which of the following animals should not be invited by the organizing committee? ——

a.Mantis. b.Locust.

c.Fly. d.Earthworm.

3. Meteors are a natural phenomenon that we are familiar with, and they can often be seen at night. The following description of meteors, the correct one is——(

a.Meteors can shine on their own, so people can see them.

b.A meteoroid is a celestial body in the Milky Way that orbits the Earth in a certain orbit.

c.Meteoroids that do not burn up fall to the ground and form meteorites.

d.Meteorites are mainly made of rock, so meteorites are also called meteorites.

4. Xiao Ming and his mother went to the supermarket to buy a drink, and found that the logo on the outer packaging of the beverage bottle was like "400ml", which should indicate the drink's - (

a.Volume. b.Quality.

c.**。d.Production time.

5. "Xiaoice Wheat" is a new wheat variety with high yield, disease resistance and high protein cultivated by the School of Life Sciences of Northeast Normal University. It is cultivated by using modern biotechnology to transfer the disease-resistant, high-protein genetic material of wild ice grass to the cells of ordinary wheat. In the cultivation process, it is mainly the operation of the structure inside the cells of wild ice grass - (

a.Cytoplasm.

b.Cell membrane.

c.Nucleus.

d.Cell wall.

6. The following statement is correct——(

a.Shiitake mushrooms belong to prokaryotes.

b.The mesophyll cells in the middle of the leaf belong to meristems.

c.Connective tissue has a variety of functions such as transportation, support, etc.

d.The pancreas does not belong to the digestive system.

A Other than that, other temperatures will hurt your hands.

c Flies can find food in people's homes, they are not very dependent on the environment, and flies are pests and should not be protected.

c Meteors are rocks or pieces of iron flying in the universe, attracted by the gravitational pull of the earth and enter the earth's atmosphere, and burn with air in the atmosphere to emit light, and those that are not burned out become meteorites or meteorites.

A ml means milliliter and is a unit of volume.

c The genetic material is in the nucleus, and the extraction and transfer of genetic material must also be placed in the nucleus to be effective.

b Mushrooms are actually generated by fungi, and fungi are eukaryotes and not prokaryotes; The connective tissue has no transport function; The pancreatic juice mainly secreted by the pancreas contains a variety of digestive juice components such as trypsin and pancreatic lipase, which is an important part of the digestive system. Only b pairs.

1.Iron and aluminum will sink to the bottom of the water, so their volume is all immersed in water, and the density of iron is greater than aluminum, in the case of equal mass, the volume of aluminum is large, so the buoyancy of aluminum is large, and the spring scale is small.

Cattle and cattle. 3.Less than, less than.

I don't know if it's right.