"Density and Social Life" Quality and Density PPT courseware download

Description

"Density and Social Life" Quality and Density PPT courseware download

The first part of the content: Practice on classification of knowledge points

Knowledge point 1 Density and temperature

1. In the physics class, the teacher brought an alcohol lamp and a paper pinwheel, hung the paper pinwheel with a thin thread and placed it above the lamp flame. After a while, the pinwheel started spinning, as shown in Figure 6-4-1. This is because: the lamp flame increases the temperature of the surrounding air,

The density changes ____, and the hot air pushes the windmill to rotate in the process of _____ (optional "rise" or "fall").

2. The body of my country's new generation space launch vehicle uses new materials with a relatively high density to increase the payload. In the event of a fire, indoor personnel should bend down and lower their body height as much as possible during the evacuation process. This is because the temperature of toxic gases increases and the volume changes, causing the density to become smaller and concentrated in the upper part of the room. (Choose "big" or "small" in both blanks)

3. When laying rails, a gap is generally left at the joint between two rails for ()

A． Prevent thermal expansion and contraction of rails

B． Reduce the thermal expansion and contraction of rails

C. The rails can expand naturally when the temperature rises, preventing the damaging effects of rail expansion.

D. Prevent the damaging effects of shrinkage when the rail temperature drops

Knowledge point 2 Abnormal expansion of water

4. Water has the property of abnormal expansion. Figure 6-4-2 shows the curve of the density of water changing with temperature in the range of 0 ~ 10 ℃. According to the image, it can be seen that when the temperature is equal to ____℃, the density of water is maximum; in the range of 0 to 4℃, water has the property of ________(optional "thermal expansion and cold expansion" or "thermal contraction and cold expansion").

5. Figure 6-4-3 shows the water temperature under the frozen lake surface. Compare the density of water in each temperature zone. Which of the following is correct? ()

A． The water density in the 0 ℃ temperature zone is the largest

B． The water density in the 2°C temperature zone is the largest

C. The density of water in the 4°C temperature zone is the highest

D. The density of water in all temperature zones under the ice surface is the same

Knowledge point 3 Density and social life

6． There are often scenes like this in some movies: a high wall collapses on everyone (actors), causing injuries. But in actual filming, the collapsed high wall will not hurt the actors. The blocks building such a high wall are most likely ()

A． Mud Bricks B. metal block

C. Styrofoam block D. cement block

7． There is a solid metal block. It is difficult to identify which metal it is from its appearance. Its volume and mass are now measured to be 5.4 cm3 and 48 g respectively. Please identify which metal it may be through the following table ()

A.Aluminum

B． copper

C. lead

D. iron

8. Human beings are always making unremitting efforts on the road to explore new materials. The world's lightest solid "aerogel" (shown in Figure 6-4-4) is an important result of the exploration of new materials. The material is strong and durable. It is as durable as steel and can withstand high temperatures of 1400°C. "Aerogel" is the lightest solid in the world, which means that its _____ (optional "density" or "mass") is small. It is known that if a large aircraft is made of "aerogel" material, the volume of "aerogel" required is 15 m3, and the mass of the aircraft is ____kg. (The density of "aerogel" is 3 kg/m3)

Density and Social Life PPT, Part 2: Comprehensive Practice of Regular Methods

10. Density knowledge is very closely related to life. Which of the following statements about density is correct ()

A． 1 kg of ice has the same density as 1 kg of water

B． The table tennis ball was accidentally crushed but not damaged. The gas density inside the ball increased.

C. To reduce mass, race bikes are made of strong, dense materials

D. To identify whether a solid metal ball is made of iron, you only need to measure its density to make an accurate judgment.

11. As shown in Figure 6-4-5, it is an aircraft independently developed by my country with independent property rights. In order to reduce the mass of the aircraft, the designer changed some steel parts into aluminum alloy parts, reducing its mass by 102 kg. The required mass of aluminum alloy is ____kg. (ρ steel = 8.0×103 kg/m3, ρ aluminum alloy = 2.0×103 kg/m3)

12. Read the passage and answer the questions at the end.

Potatoes, commonly known as potatoes, are widely loved for their many advantages such as strong growth adaptability, high yield, and various cooking methods. Potatoes are rich in starch and are an important raw material for the production of starch. Xiao Ming participated in comprehensive practical activities in the starch factory. He followed the worker master to purchase a batch of potatoes with a starch content of no less than 20%. The following table is some data collected by Xiao Ming that reflects potato-related information. At the purchasing point, Xiao Ming measured the mass of a potato to be 0.22 kg and the volume to be 200 cm3, and was going to use this to determine whether the potato met the factory's purchasing requirements.

(1) Draw the relationship between potato density and starch content in coordinate chart 6-4-6.

(2) It can be seen from the image that the higher the starch content in potatoes, the ____ the density.

(3) Does the potato measured by Xiao Ming meet the factory’s purchasing requirements? _______ (optional "conforms" or "does not conform").

(4) Potatoes with high starch content also have high prices. Among the potato varieties that meet the factory's purchasing requirements, the one that is relatively cheap and has a high flour extraction rate is ____ (fill in the variety number).

13. Xiao Ming's mother bought a gold ring. In order to know whether this gold ring is pure gold (the density of gold is 19.3×103 kg/m3), Xiao Ming measured the mass of the ring to be 7.8 g and the volume to be 0.5 cm3. Please use calculations to determine whether this ring is pure gold.

14. There is an iron ball with a mass of 237 g and a volume of 80 cm3. (ρ iron = 7.9×103 kg/m3, ρ water = 1.0×103 kg/m3)

(1) Please prove through calculation that the iron ball is hollow.

(2) What is the volume of the hollow part?

(3) If the hollow part of the iron ball is filled with water, what is the total mass of the entire iron ball?

Keywords: Free download of PPT courseware for eighth-grade physics volume 1 of the People's Education Press, PPT download of density and social life, PPT download of quality and density, .PPT format;

For more information about the PPT courseware "Quality and Density Density and Social Life", please click the Quality and Density ppt Density and Social Life ppt tag.

"Integration of this Chapter" Quality and Density PPT:

"Integration of this Chapter" Mass and Density PPT High School Entrance Examination Focused Experience 1. (2018 Shandong Zaozhuang High School Entrance Examination) The factor that determines the mass of an object is ( ) A. The amount of matter contained in the object B. The shape of the object C. The state of the object D. The object The spatial location is 2. (2018 Hunan..

"Density and Social Life" Quality and Density PPT teaching courseware:

"Density and Social Life" Quality and Density PPT Teaching Courseware Part One Content: New Knowledge - Density and Temperature 1. The relationship between density and temperature. The density of substances is related to temperature. Most substances follow the law of ______, but water is more special. 2. Thermal expansion..

"Density and Social Life" Quality and Density PPT download:

"Density and Social Life" Quality and Density PPT Download Part One: Basic Knowledge Points Knowledge Point 1 Density and Temperature 1. Water has the characteristic of abnormal expansion. The picture shows the -t image of water with a mass of 1 g under standard atmospheric pressure. According to the image, it can be seen that the temperature is equal to 4..

File Info

Update Time: 2024-07-29

This template belongs to Physics courseware People's Education Edition Physics for Grade 8, Volume 1 industry PPT template

Preview