Which of the following is true of thermal phenomena? Thermal phenomena test

Mass of molecules

Molecules- these are the smallest particles of many substances, composition and Chemical properties which are the same as those of this substance. Any substance consists of particles, therefore the amount of substance is considered to be proportional to the number of particles. The unit of quantity of a substance is the mole. A mole is equal to the amount of substance in a system containing the same number of particles as are contained in atoms in carbon weighing 12 g. The ratio of the number of molecules to the amount of substance is called Avogadro's constant.

The molar mass of a substance is equal to the ratio of the mass of the substance to the corresponding amount of the substance:

Brownian motion: Brownian motion is the movement of particles suspended in a gas or liquid. In 1827, the English botanist Brown discovered the random movement of solid particles visible through a microscope in a liquid.

This phenomenon was called Brownian motion. This movement does not stop: as the movement increases, its intensity increases. Brownian motion is the result of fluctuation (a noticeable deviation from the average value). The reason for the Brownian motion of a particle is that the collisions of molecules in a liquid with the particle do not cancel each other out.

Control questions.

1. Define thermal phenomena.

2. What is thermal motion?

3. What is the significance of thermal phenomena?

4. Estimate the size of the molecules.

5. In what units is the mass of molecules measured?

Option I

1. What energy does the mechanical energy of a lead ball transform into when it hits a lead plate?

A) energy becomes equal to 0;

B) mechanical energy turns into internal energy;

C) mechanical energy increases.

2. Which of the following substances have the lowest thermal conductivity?

A) hard; B) liquid; B) gaseous; D) solid and liquid.

3. A cold metal spoon was dipped into a glass of hot water. Has the internal energy of the spoon changed, and if so, in what way?

A) increased by doing work;

B) decreased due to work being done;

B) increased due to heat transfer; D) has not changed.

4. In which of the following substances can convection occur?

A) in solids; B) in liquid; B) in gaseous; D) in gaseous and liquid.

5. In which of the following substances does heat transfer occur mainly by thermal conductivity?

A) air;

B) brick;

6. How can you change the internal energy of the body?

A) only by performing work; B) only by heat transfer;

C) the performance of work and heat transfer.

7. How is energy transferred from the Sun to the Earth?

A) thermal conductivity;

B) radiation;

B) convection;

D) work.

8. What type of heat transfer is not accompanied by the transfer of matter?

A) convection only;

B) thermal conductivity only;

B) only radiation and convection.

9. Which of the following substances has good thermal conductivity?

A) glass;

To the air;

10. In what case will the internal energy of water change?

A) carry water in a bucket;

B) pour water from a bucket into a kettle;

C) heat the water to a boil.

11. What is thermal motion called?

A) ordered movement of a large number of molecules;

B) continuous random movement of a large number of molecules;

IN) rectilinear movement a single molecule.

12. Which of the following is the definition of internal energy?

A) the energy that a body possesses due to its movement;

B) energy, which is determined by the position of interacting bodies or parts of one body;

C) the energy of movement and interaction of the particles that make up the body.

13. What physical quantities does the internal energy of a body depend on?

A) on the mass and speed of the body;

B) on height above the ground and speed;

C) on temperature and body weight.

14. The copper wire clamped with pliers is bent and unbent several times. Will the internal energy change, and if so, in what way?

A) yes by heat transfer;

B) yes, by doing work;

B) yes, by heat transfer and work;

D) will not change.

15. What physical phenomenon is used for the design and operation of a mercury thermometer?

A) melting of a solid when heated;

B) convection in a liquid when heated;

B) expansion of a liquid when heated;

D) evaporation of liquid.

OPTION 1

1). body falling to Earth 2). heating a pan 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 internal energy

A. All bodies B. Only solids C. Only liquids D. Only gases

How can you change the internal energy of the body?

A. Heat transfer. B. By doing work. B. Heat transfer and work. D. The internal energy of the body cannot be changed.

A. Heat transfer. B. By doing work. B. Heat transfer and work. D. The internal energy of the plate does not change.

What type of heat transfer is accompanied by the transfer of matter?

A. Convection only. B. Thermal conductivity only. B. Radiation only.

D. Convection and thermal conductivity. D. Convection and radiation.

E. Convection, thermal conductivity, radiation. G. Thermal conductivity, radiation.

OPTION-2

Which of the following examples relate to thermal phenomena?

1) evaporation of liquid 2) echo 3) inertia 4) gravity 5) diffusion

A. 1, 3 B. 1, 4 C. 1, 5 D. 2, 4 C. All

The internal energy of a body depends on

A. Mechanical movement of the body B. Position of the body relative to other bodies C. movement and interaction of particles of the body D. Mass and density of the body.

Can the internal energy of a body change during work and heat transfer?

A. The internal energy of the body cannot change. B. Can only when doing work. B. It can only with heat transfer. D. Can during work and heat transfer.

A. Heat transfer. B. By doing work. B. Heat transfer and work. D. The internal energy of the wire does not change.

What type of heat transfer is not accompanied by the transfer of matter?

A. Radiation. B. Convection. B. Thermal conductivity. D. Radiation, convection, thermal conductivity. D. Radiation, convection. E. Radiation, thermal conductivity.

G. 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 yes, then in what way?

Why do many plants die in snowless winters, while they can withstand significant frosts if the snow cover is large?

The spacesuits worn by astronauts are usually colored White color. At the same time, some surfaces spaceships black. What explains the choice of color?

When is the fastest time for a kettle of boiling water to cool down: when is it put on ice or when ice is placed on the lid of the kettle?

Why do many animals sleep curled up in a ball in cold weather?

Option 2

The 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?

Scissors and a pencil lying on the table have the same temperature. Why do scissors feel colder to the touch?

Why does snow covered with soot or dirt melt faster than clean snow?

In industrial refrigerators, air is cooled using pipes through which cooled liquid flows. Where is the best place to place these pipes?

a) if it is widely known

a) only in gaseous

b) in gaseous and liquid

c) in all conditions

d) in no condition

1) which of the following refers to physical phenomena? a) molecule b) melting c) kilometer d) gold

2) which of the following is a physical quantity?

a) second b) force c) melting d) silver

3) what is the basic unit of mass in international system units?

a) kilogram b) newton c) watt d) joule

4) in what case in physics is a statement considered true?

a) if it is widely known

d) if it has been experimentally tested many times by different scientists

5) in which state of the substance at the same temperature the speed of movement of molecules is greater?

a) in solid b) in liquid c) in gas d) in all the same

6) in what state of matter is the speed of random movement of molecules decreases with decreasing temperature?

a) only in gaseous

b) in gaseous and liquid

c) in all conditions

d) in no condition

7) the body retains its volume and shape. What state of aggregation is it in? the substance from which the body is made?

a) in liquid b) in solid c) in gas c) in any state

Help) But we need it 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 consist of molecules. C) Only gases consist of molecules. D) All bodies are made of molecules.

3) In what media does diffusion occur?

A) Only in gases.. B) Only in liquids. B) Only in solids. D) In ​​gases and liquids. D) In ​​liquids and solids. E) In gases and solids. G) In gases, liquids and solids.

4) Does the speed of movement of molecules change as the temperature of a substance increases?

A) Does not change. B) Decreases. B) It increases. D) It changes only for gases. D) It changes only for 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. D) 1.3. E) 2.3. G) 1,2,3

6) The car covered a distance of 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) How far will a cyclist travel 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 a pedestrian to cover a distance of 1200 m, moving at a speed of 2 m/s?

A) 600 s. B) 2400 s. B) 600 min. D) 6 hours.

8. The tram moves at a speed of 36 km/h. What distance in meters will he travel in 720 seconds?

9. During the flight, a flock of 30 birds covered 15 km in 30 minutes. Determine the average speed of 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 takes up half the volume of a three-liter bottle. What volume does gas occupy in SI units?
18. The pictures show a beaker with kerosene and a lead weight weighing 113 g. Determine the volume of liquid in the beaker after lowering the weight into it. Lead density 11.3 g/cm3 (photo below)
19. Convert 100 mm2 to cm2.
20. Which of the following relates to thermal phenomena?
21. Before the lesson, the physics teacher selected a copper wire of the required diameter. To do this, he wound it tightly around the rod. The number of turns obtained from 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 your answer to the nearest whole number (photo below)
23. At night the air temperature was -4°C, and during the day it rose to 4°C. Determine the difference between these temperatures.
27. What formula is used to calculate the density of a substance through the mass of the molecule (m0) and concentration n?
28. Which of the following quantities are vector quantities? (Strength, density, speed, mass)
29. Which of the listed forces is always directed towards the center of the earth?
30. What formula is used to calculate the elastic force of a deformed body in physics?
Whatever you can, please.