"Conditions and Applications of Floating and Sinking Objects" Buoyancy PPT (Lesson 1)

Description

"Conditions and Applications of Floating and Sinking Objects" Buoyancy PPT (Lesson 1)

Part One Content: Basic Knowledge Key Points

Knowledge point 1: The relationship between the floating and sinking of objects and buoyancy

1. A 50 kg man is lying on the Dead Sea reading a book. The buoyancy force he experiences is 500 N (g is 10 N/kg).

2. Three objects A, B, and C with the same volume but different materials are immersed in the same liquid. Their stress conditions are as shown in the figure. Then the floating object is C and the sinking object is B (please fill in "A", "B" or "C").

3. The mass of an object is 2 kg, and the buoyancy force it receives when it is immersed in water is 30 N. When you let go of your hand, the object will be (A)

A. Floating B. Suspension

C. sinking D. unable to judge

4. Put small iron blocks and small wooden blocks into a basin of water. It was found that the wooden block floated on the water and the iron block sank to the bottom. The following analysis of this phenomenon is correct (B)

A. The wooden block is subject to buoyancy, while the iron block is not subject to buoyancy.

B. When an iron block sinks to the bottom of the water, the buoyant force it experiences must be less than its own gravity.

C. The buoyant force on the wooden block must be greater than the buoyant force on the iron block

D. The wooden block floats on the water, and the buoyant force is greater than its own gravity.

Knowledge point 2: The relationship between the floating and sinking of objects and their density

5. Xiaohong likes to do experiments with her hands. After learning the floating and sinking conditions of objects, she did the experiment as shown in the picture. She put the same egg into two cups of salt water A and B, and got the relationship between density and buoyancy: the density relationship of salt water is ρA > ρB, and the buoyancy force on the egg is FA = FB (all Optional ">" "<" or "=").

6. An object with uniform density is suspended in water. If it is cut in half, it will be (C)

A.Float B.Sink

C. Suspension D. All of the above are possible

7. Put an object weighing 5 N and having a volume of 0.6 dm3 into alcohol (the density of alcohol is 0.8×103 kg/m3). Ignoring the resistance of alcohol, when the object is stationary, which of the following statements is correct (D)

A. The object floats, F float = 5 N

B. The object floats, F float = 4.8 N

C. The object sinks to the bottom, F floats = 5 N

D. The object sinks to the bottom, F floats = 4.8 N

Floating and sinking conditions of objects and application PPT, part 2: improvement of comprehensive capabilities

8. As shown in the figure, insert a small iron nail into the lower end of an unlit cylindrical candle so that the candle can float upright in the water. Slowly add an appropriate amount of salt to the water, and the buoyancy force on the candle will remain unchanged. , the pressure of the liquid on the lower surface of the cylindrical candle will remain unchanged (choose "get bigger", "get smaller" or "unchanged").

9. When Xiao Ming made tea in a glass cup, he discovered that when the tea was first brewed, the tea leaves were floating on the water. At this time, the buoyancy force on the tea leaves was equal to gravity. After a while, because the tea leaves absorbed water, the average density of the tea leaves was greater than the density of water. And sink to the bottom of the cup (please fill in "greater than", "less than" or "equal to").

10. There is an iceberg in the floating ice area, and its volume exposed to the sea is 100 m3. The buoyancy force on the iceberg is 4.95×106N, and the volume of its underwater part is 450m3 (ρ seawater = 1.1×103 kg/m3, ρ ice =0.9×103 kg/m3, g is 10 N/kg).

11. As shown in the figure, two identical containers A and B contain different types of liquids. Now put two identical blocks into the two containers respectively. When the two blocks finally come to rest, the liquid in the two containers will The surfaces are exactly flat, then the correct one of the following statements is (B)

A. The density of the liquid in container A is greater

B. The bottom of container B is under greater pressure from the liquid

C. The gravity of the liquid displaced by the objects in container A is greater

D. The object in container B is buoyant by the liquid.

12. The water level changes of seawater can be monitored by placing buoys. From spring to summer, the temperature of seawater rises and the volume expands, causing the density to decrease. During this process, if the volume of the buoy remains unchanged, then (C)

A. The buoyancy force increases and the volume exposed to the sea surface decreases.

B. The buoyancy becomes smaller and the volume exposed to the sea surface becomes larger.

C. The buoyancy remains unchanged and the volume exposed to the sea surface becomes smaller.

D. The buoyancy remains unchanged and the volume exposed to the sea surface increases.

The floating and sinking conditions and application of objects PPT, the third part of the content: Expanding exploration and breakthroughs

18. After learning the knowledge of buoyancy, almost all the students were convinced that the wooden block would float on the water. Only Xiaofeng still had doubts about this. After some debate, he found some equipment and did the following Experiment (g is taken as 10 N/kg).

(1) He puts a cube wooden block with a side length of 10 cm and a density of 0.6×103 kg/m3 into the sink, and then adds 5 cm of water to the water. Please calculate whether the wooden block can float;

(2) Continue to add water to the tank until the water depth reaches 10 cm. Can the wooden block float on the water at this time? What is the pressure of the water on the bottom of the tank at this time?

Keywords: Free download of PPT courseware for the second volume of eighth-grade physics from the People's Education Press, PPT download of the floating and sinking conditions of objects and their applications, PPT download of buoyancy, PPT download of the floating and sinking conditions of objects, .PPT format;

For more information about the "Floating and sinking conditions of buoyant objects and floating and sinking conditions of applied objects" PPT courseware, please click on the "Floating and sinking conditions of buoyant ppt objects and floating and sinking conditions of applied ppt objects" ppt tag.

"Conditions and Applications of Floating and Sinking Objects" Buoyancy PPT (Lesson 2):

"Floating and Sinking Conditions and Applications of Objects" Buoyancy PPT (Lesson 2) Part One: Basic Knowledge Points Knowledge Point 1 Ship 1. Ships use the hollow method to increase the available buoyancy, which is the application of floating conditions. The displacement of a ship is 1103 t, then this ship...

Download "Floating and Sinking Conditions and Applications of Objects" Buoyancy PPT:

"The Floating and Sinking Conditions and Applications of Objects" Buoyancy PPT Download Part One Content: Preview Perception 1. The Floating and Sinking Conditions of Objects Floating and sinking types F float and G Relationship between liquid and object Floating (as shown in Figure A) F floating G Liquid sinking (as shown in Figure A) B) F float G liquid suspension (as shown in Figure C) F..

"Conditions and Applications of Floating and Sinking Objects" Buoyancy PPT:

"The Floating and Sinking Conditions and Applications of Objects" Buoyancy PPT Part One Content: Learning Objectives Navigation Learning Objectives 1. Understand the floating and sinking conditions of objects and be able to use them to solve practical problems. 2. Understand the principles of floating and sinking of ships, balloons, motorboats, and submarines. Learning key points...

File Info

Update Time: 2024-10-03

This template belongs to Physics courseware People's Education Edition Physics for Grade 8, Volume 2 industry PPT template

Preview