OPTION 1
1). the fall of the body to the Earth 2). heating a pot of water 3) melting ice 4) reflection of light 5) movement of one molecule
A. 1, 2 and 5 B. 2, 3, 5 C. 2, 3 D. 2, 4 E. 1, 5 E. All
They have inner energy
A. All bodies B. Only solids C. Only liquids D. Only gases
How can the internal energy of the body be changed?
A. Heat transfer. B. By doing work. B. Heat transfer and performance of work. D. The internal energy of the body cannot be changed.
A. Heat transfer. B. By doing work. B. Heat transfer and performance of work. D. The internal energy of the plate does not change.
What kind of heat transfer is accompanied by the transfer of matter?
A. Convection only. B. Only thermal conductivity. B. Radiation only.
D. Convection and heat conduction. D. Convection and radiation.
E. Convection, heat conduction, radiation. G. Thermal conductivity, radiation.
OPTION-2
Which of the following examples are related to thermal phenomena?
1) evaporation of liquid 2) echo 3) inertia 4) gravity 5) diffusion
A. 1, 3 B. 1, 4 C. 1, 5 G. 2, 4 C. All
The internal energy of the body depends on
A. Mechanical motion of the body B. Position of the body relative to other bodies C. Movement and interaction of body particles D. Masses and density of the body.
Can the internal energy of the body change during the performance of work and heat transfer?
A. The internal energy of the body cannot change. B. Can only when doing work. B. It can only be with heat transfer. D. Can when doing work and heat transfer.
A. Heat transfer. B. By doing work. B. Heat transfer and performance of work. D. The internal energy of the wire does not change.
What kind of heat transfer is not accompanied by material transfer?
A. Radiation. B. Convection. B. Thermal conductivity. D. Radiation, convection, thermal conductivity. D. Radiation, convection. E. Radiation, thermal conductivity.
J. Convection, thermal conductivity.
Option 1
The copper wire clamped with pliers is bent and unbent several times. Does this change the internal energy of the wire? If so, in what way?
Why do many plants die during snowless winters, while they can withstand significant frosts if the snow cover is large?
Spacesuits worn by astronauts are usually painted in white color... At the same time, some surfaces spaceships black. What explains the choice of color?
When will the kettle with boiling water cool down sooner: when was it put on ice or when was the ice put on the lid of the kettle?
Why do many animals sleep curled up in a ball in cold weather?
Option 2
A steel plate was placed on a hot electric stove. In what way does the internal energy of the plate change?
Why can you burn your hands when sliding quickly down a rope or pole?
The scissors and pencil on the table are at the same temperature. Why does the scissors feel colder to the touch?
Why does snow that is covered in soot or mud melt faster than clean snow?
In industrial refrigerators, the air is cooled by pipes through which chilled liquid flows. Where is the best place to place these pipes?
The text of the work is placed without images and formulas.
The full version of the work is available in the "Work files" tab in PDF format
Hypothesis:thanks to scientific knowledge and achievements, lightweight, durable low-heat materials for clothing and home protection, air conditioners, fans and other devices have been created. This allows us to overcome the difficulties and many problems associated with heat. But nevertheless, it is necessary to study thermal phenomena, since they have exclusively big influence on our lives.
Goal: study of thermal phenomena and thermal processes.
Tasks: talk about thermal phenomena and thermal processes;
study the theory of thermal phenomena;
in practice, consider the existence of thermal processes;
show the manifestation of these experiences.
Expected Result:conducting experiments and studying the most common thermal processes.
: selected and systematized material on the topic, conducted experiments and blitz - a survey of students, prepared a presentation, presented a poem of his own composition.
Thermal phenomena are physical phenomena that are associated with the heating and cooling of bodies.
Heating and cooling, evaporation and boiling, melting and solidification, condensation are all examples of thermal phenomena.
Thermal motion -chaotic (disordered) movement process
particles forming the substance.
The higher the temperature, the faster the particles move. The thermal motion of atoms and molecules is most often considered. Molecules or atoms of a substance are always in constant disorderly motion.
This movement determines the presence of internal kinetic energy in any substance, which is associated with the temperature of the substance.
Therefore, the disorderly motion, in which there are always molecules or atoms, is called thermal.
The study of thermal phenomena shows that how much in them decreases mechanical energy bodies, their mechanical and internal energies increase to the same extent, remains unchanged in any processes.
This is the law of conservation of energy.
Energy does not arise from nothing and does not disappear anywhere.
It can only pass from one type to another, retaining its full meaning.
Thermal movement of molecules never stops. Therefore, any body always has some kind of internal energy. Internal energy depends on the temperature of the body, the state of aggregation of matter and other factors and does not depend on the mechanical position of the body and its mechanical movement. Changing the internal energy of the body without doing work is called heat transfer .
Heat transfer always occurs in the direction from a body with a higher temperature to a body with a lower temperature.
There are three types of heat transfer:
Thermal processes are a kind of thermal phenomena; processes in which the temperature of bodies and substances changes, and it is also possible to change them aggregate states... Thermal processes include:
Heating
Cooling
Steam generation
Boiling
Evaporation
Crystallization
Melting
Condensation
Combustion
Sublimation
Desublimation
Consider, as an example, a substance that can be in three states of aggregation: water (L - liquid, T - solid, G - gaseous)
Heating - the process of increasing the temperature of the body or substance. Heating is accompanied by the absorption of heat from the environment. When heated, the state of aggregation does not change.
Experience 1: Heating.
Take water from a tap into a glass and measure its temperature (25 ° C),
then put the glass on a warm place (window on the sunny side), and after a while measure the water temperature (30 ° C).
After waiting some more time, I again measured the temperature (35 ° C). Conclusion: the thermometer shows an increase in temperature, first by 5 ° C, and then by 10 ° C.
Cooling - the process of lowering the temperature of a substance or body; Cooling is accompanied by the release of heat into the environment. When cooled, the state of aggregation does not change.
Experience 2: Cooling. Let's see how cooling occurs experimentally.
From the tap into the glass we will collect hot water and measure its temperature (60 ° C), then put this glass on the windowsill for a while, after which we measure the temperature of the water and it became equal (20 ° C).
Conclusion: the water is cooled and the thermometer shows a decrease in temperature.
Test 3: Boiling.
We encounter boiling at home every day.
Pour water into the kettle and put it on the stove. From the beginning, the water heats up, and then the water boils. This is evidenced by the steam coming out of the teapot spout.
Conclusion: when boiling water, steam from the neck of the kettle comes out through a small hole and whistles and we turn off the stove.
Evaporationis vaporization that occurs with free surface liquids.
Evaporation depends on:
Substance temperatures (the higher the temperature, the more intense the evaporation);
Liquid surface areas (the larger the area, the greater the evaporation);
The kind of substance (different substances evaporate at different rates);
The presence of wind (evaporation is faster in the presence of wind).
Test 4: Evaporation.
If you have ever observed puddles after rain, then you have undoubtedly noticed that the puddles are getting smaller and smaller. What happened to the water?
Conclusion: she vanished!
Crystallization (solidification) is the transition of a substance from a liquid state of aggregation to a solid. Crystallization is accompanied by the release of energy (heat) into the environment.
Test 5: Crystallization. To detect crystallization, let's conduct an experiment.
Take water from the tap into a glass and put it in the freezer of the refrigerator. After a while, the process of solidification of the substance occurs, i.e. a crust appears on the surface of the water. Then all the water in the glass completely turned into ice, that is, it crystallizes.
Conclusion: first, the water is cooled to 0 degrees, then freezes.
Melting - transition of matter from solid state into liquid. This process is accompanied by the absorption of heat from the environment. To melt a solid crystalline body, it needs to transfer a certain amount of heat.
Experience 6: Melting. Melting is easily detected experimentally.
We take out a glass of frozen water from the freezer compartment of the refrigerator, which we put. After a while, water appeared in the glass - the ice began to melt. After some time, all the ice melted, that is, it completely passed from solid to liquid.
Conclusion: ice gains heat from the environment over time and will melt over time.
Condensation -transition of a substance from a gaseous state to a liquid.
Condensation is accompanied by the release of heat into the environment.
Test 7: Condensation.
We boiled water and brought a cold mirror to the spout of the kettle. After a few minutes, drops of condensed water vapor are clearly visible on the mirror.
Conclusion: the vapor settling on the mirror turns into water.
The condensation phenomenon can be observed in the summer, in the early cool morning.
Droplets of water on grass and flowers - dew - indicate that the water vapor contained in the air has condensed.
Combustion is the process of burning fuel, accompanied by the release of energy.
This energy is used in various
spheres of our life.
Experience 8: Combustion. Every day we can watch how natural gas burns in the stove burner. This is the process of fuel combustion.
Also, the process of fuel combustion is the process of burning wood. Therefore, in order to conduct an experiment on fuel combustion, it is enough only to ignite the gas
burner or match.
Conclusion: when fuel is burned, heat is generated, a specific odor may appear.
The result of work on the project: In my design work, I studied the most common thermal processes: heating, cooling, vaporization, boiling, evaporation, melting, crystallization, condensation, combustion, sublimation and desublimation.
In addition, the work touched on such topics as thermal motion, states of aggregation, as well as the general theory of thermal phenomena and thermal processes.
One or another thermal phenomenon was considered on the basis of the simplest experiments. The experiments are accompanied by demo pictures.
Based on the experiments, it was considered:
The existence of various thermal processes;
the relevance of thermal processes in human life has been proven.
I also conducted a blitz survey of students in the 9 "A" class, consisting of 15 people.
Blitz - a survey of students in grade 9.
Questions:
1. What are thermal phenomena?
2. Give examples of thermal phenomena
3. What movement is called heat?
4. What is thermal conductivity?
5. Aggregate transformations are ...
6. Phenomenon of transformation of liquid into vapor?
7. The phenomenon of transformation of vapor into liquid?
8. What process is called melting?
9. What is evaporation?
10. What are the processes reverse to heating, melting, evaporation?
Answers:
1. Thermal phenomena - physical phenomena associated with heating and cooling of bodies
2. Examples of thermal phenomena: heating and cooling, evaporation and boiling, melting and solidification, condensation
3. Thermal movement - a disorderly, chaotic movement of molecules
4. Thermal conductivity - transfer of heat from one part to another
5. Aggregate transformations are the phenomena of the transition of a substance from one state of aggregation to another
6. Steam generation
7. Condensation
8. Melting - the transition of a substance from a solid to a liquid state. This process is accompanied by the absorption of heat from the environment.
9. Evaporation is vaporization that occurs from the free surface of a liquid
10. Processes reverse to heating, melting, evaporation - cooling, crystallization, condensation
Blitz poll results:
1. Correct answer - 7 people - 47%
Wrong answer - 8 people - 53%
2. Correct answer -6 people - 40%
Wrong answer -9 people - 60%
3. Correct answer - 10 people - 67%
4. Correct answer -6 people - 40%
Wrong answer - 9 people - 60%
5. Correct answer - 8 people - 53%
6. Correct answer - 12 people - 80%
Wrong answer - 3 people - 20%
7. Correct answer - 8 people - 53%
Wrong answer - 7 people - 47%
8. Correct answer - 10 people - 67%
Wrong answer - 5 people - 33%
9. Correct answer - 13 people - 87%
Wrong answer - 2 people - 13%
10. The correct answer is 8 people -53%
Wrong answer - 7 people - 47%
The blitz survey showed that the students are not familiar enough with this topic, and I hope that my project will help them fill in the missing gaps on this topic.
My goal and objectives design work completed.
I want to finish my work with a poem that we wrote together with my grandfather.
Thermal phenomena
We study phenomena
We wish to learn about warmth.
We live in a wonderful world -
Everything is like two and two - four.
We do the work
Swinging the molecules of the mouth,
A log for firewood -
We feel warm.
A very important task-
This is heat transfer.
Heat can be transferred
Take from heated water.
All bodies are thermally conductive:
The water heats the radiator
The air goes up from the bottom
It transfers warmth to the house.
And the window glass
Keeps warmth in the house.
There is an air layer in the frame -
For warmth it is a mountain.
It does not let heat through
And keeps it in the apartment.
Well, in the afternoon, we know ourselves
The sun will give warmth with rays ...
To know all these properties,
To live in friendship with warmth in the world,
And actually apply -
It is necessary to teach a PHYSICIAN !!!
List of references
1. Rakhimbaev M.M. Flash textbook: “Physics. 8th grade". 2. Teaching physics that develops the student. Book 1. Approaches, components, lessons, tasks / Compiled and ed. EM. Braverman: - M .: Association of Physics Teachers, 2003. - 400 p. 3. Dubovitskaya T. D. Diagnostics of the importance of the subject for the development of the personality of students. OSU Bulletin, No. 2, 2004. 4. Kolechenko A.K. Encyclopedia of Educational Technologies: A Guide for Educators. - SPb .: KARO, 2004. 5. Selevko G.K. Pedagogical technologies on the basis of activation, intensification and effective management of EPP. Moscow: Research Institute of School Technologies, 2005. 6. Electronic resources: Website http://school-collection.edu.ru Website http://obvad.ucoz.ru/index/0 Website http://zabalkin.narod.ru Website http://somit.ru
a) if it is widely known
a) only in gaseous
b) in gaseous and liquid
c) in all states
d) in no state
1) which of the following is a physical phenomenon? a) molecule b) melting c) kilometer d) gold2) which of the following is physical size?
a) second b) strength c) melting d) silver
3) what is the basic unit of mass in the international system of units?
a) kilogram b) newton c) watt d) joule
4) in what case is the statement considered true in physics?
a) if it is widely known
d) if it is repeatedly experimentally tested by different scientists
5) in what state of matter at the same temperature is the speed of movement of molecules greater?
a) in solid b) in liquid c) in gaseous d) in all the same
6) in what state of matter is the rate of random movement of molecules decreases with decreasing temperature?
a) only in gaseous
b) in gaseous and liquid
c) in all states
d) in no state
7) the body retains its volume and shape. What is the state of aggregation the substance of which the body is made up?
a) in liquid b) in solid c) in gaseous c) in any state
Help) But urgently 1) Which of the following is a physical body? (1. Hurricane. 2. Water. 3. Knife) A) 1. B) 2. C) 3. D) 1.2. D)1.3. E) 2.3. G) 1,2,3
2) Choose the correct statement:
A) Only solids are made up of molecules. B) Only liquids are made up of molecules. C) Only gases are composed of molecules. D) All bodies are composed of molecules.
3) In what media does diffusion occur?
A) Only in gases .. B) Only in liquids. C) Only in solids... D) In \u200b\u200bgases and liquids. E) In liquids and solids. E) In gases and solids. G) In gases, liquids and solids.
4) Does the speed of movement of molecules change with increasing temperature of the substance?
A) Does not change. B) Decreases. C) Increases. D) Changes only in gases. E) Changes only in molecules of liquids and gases.
5) Which of the following is a substance? (1. Iron. 2. Rope. 3. Paper)
A) 1. B) 2. C) 3. D) 1.2. E) 1.3. E) 2.3. G) 1,2,3
6) The car traveled 200 m in 10 seconds. What is its speed?
A) 2000 m / s. B) 20 m / s. B) 2 m / s. D) 2 km / h. D) 20 km / h.
7) What distance will a cyclist travel, moving at a speed of 5 m / s in 20 s?
A) 4 m. B) 100 m. C) 100 km.
8) How long will it take for a pedestrian to travel 1200 m, moving at a speed of 2 m / s?
A) 600 s. B) 2400 s. C) 600 min. D) 6 h.
8. The tram is moving at a speed of 36 km / h. What distance in meters will it cover in 720 seconds?9. During the flight, a flock of 30 birds covered 15 km in 30 minutes. Define average speed one bird in km / h.
10. What is the mass of gasoline in a five-liter can? (Density 0.71 g / cm3)
14. How many millimeters are in three meters?
17. Gas occupies half the volume of a three-liter bottle. What is the volume of gas in SI units?
18. The figures show a beaker with kerosene and a lead weight of 113 g. Determine the volume of liquid in the beaker after lowering the weight into it. The density of lead is 11.3 g / cm3 (photo below)
19. Convert 100 mm2 to cm2.
20. Which of the following refers to thermal phenomena?
21. The physics teacher before the lesson selected a copper wire of the required diameter. To do this, he wound it tightly on a rod. The number of turns obtained by the teacher turned out to be 30 pieces, with a total length of 15 cm. Determine the diameter of the wire in mm.
22. Determine the mass of the part shown in the figure if its density is 7.6 g / cm3. Round the answer to the nearest whole (photo below)
23. At night the air temperature was -4 ° С, and during the day it rose to 4 ° С. Determine the difference in these temperatures.
27. What is the formula for calculating the density of a substance through the mass of the molecule (m0) and the concentration n?
28. Which of the following items are vector? (Force, density, speed, mass)
29. Which of the following forces is always directed to the center of the earth?
30. By what formula is the elastic force of a deformed body calculated in physics?
What you can, please.