Unified State Examination in Physics, 2003
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Part A

A1. The figures show graphs of the dependence of the acceleration module on the time of movement. Which of the graphs corresponds to uniform rectilinear motion?

1)		2)
3)		4)

Solution. In uniform rectilinear motion, the acceleration is zero.

Correct answer: 2.

A2. Rocket engine of the first domestic experimental rocket on liquid fuel had a thrust force of 660 N. The launch mass of the rocket was 30 kg. What is the acceleration of the rocket during launch?

Solution. There are two forces acting on the rocket: gravity ( mg) directed downwards, and the thrust force ( F) directed upwards. According to Newton's second law:

Correct answer: 1.

A3. With a 3-fold increase in the distance between the centers of spherical bodies, the force of gravitational attraction

Solution. The force of gravitational attraction of two spherical bodies is equal to

.

With a 3-fold increase in the distance between their centers, the force of gravitational attraction decreases by 9 times.

Correct answer: 4.

A4. The figure shows a thin weightless rod, to which forces and are applied at points 1 and 3. At what point should the axis of rotation be located in order for the rod to be in equilibrium?

Solution. The equilibrium condition for the rod is the equality , where and are the distances from the axis of rotation to the points of application of forces. Since the second force is 3 times the first, its point of application must be 3 times closer to the axis of rotation. This means that the axis of rotation is located either at point 2.5 or at point 4. If the axis of rotation is at point 2.5, then the forces rotate the rod in one direction and do not balance each other. When the axis of rotation is located at point 4, the forces rotate the rod in different directions, balancing each other.

Correct answer: 3.

A5. A boy threw a soccer ball weighing 0.4 kg to a height of 3 m. How much has the potential energy of the ball changed?

Solution. In general, with harmonic vibrations, the coordinate of the body changes according to the law , where A - oscillation amplitude, ω - cyclic oscillation frequency. The oscillation amplitude is 0.9 m.

Correct answer: 3.

A7. The human ear can perceive sounds with a frequency of 20 to 20,000 Hz. What range of wavelengths corresponds to the interval of audibility of sound vibrations? Take the speed of sound in air equal to 340 m/s.

Solution. The wavelength λ is related to the oscillation frequency ν by the relation , where v- wave propagation speed. The minimum wavelength of audible sound vibrations is

,

and the maximum wavelength of audible sound vibrations is equal to

.

Correct answer: 4.

A8. Diffusion occurs faster as the temperature of a substance increases, because

Solution. As the temperature rises, diffusion occurs faster due to an increase in the speed of particle movement.

Correct answer: 1.

A9. At a constant concentration of particles of an ideal gas, the average kinetic energy thermal motion of its molecules increased by 3 times. At the same time, the gas pressure

Solution. According to the basic equation of molecular kinetic theory, the pressure of an ideal gas p related to concentration n and the average kinetic energy of the movement of its molecules by the ratio:

At a constant particle concentration and a 3-fold increase in their average kinetic energy, the pressure increases 3-fold.

Correct answer: 2.

A10. The figure shows a graph of the dependence of gas pressure on the vessel walls on temperature. What process of changing the state of a gas is depicted?

Solution. The figure shows an isochoric process that went in the direction of decreasing temperature. So, the figure shows isochoric cooling.

Correct answer: 2.

A11. When a solid body is cooled m body temperature dropped by Δ T. Which of the following formulas should be used to calculate the amount of heat given off by the body Q? c is the specific heat capacity of the substance.

Solution. The amount of heat given off by the body is calculated by the formula.

Correct answer: 1.

A12. Internal energy of an ideal gas when it is cooled

Solution. The internal energy of an ideal gas is , where is the heat capacity of the gas at a constant volume, T- his temperature. The heat capacity of an ideal gas does not depend on temperature. As the temperature decreases, the internal energy of an ideal gas decreases.

Correct answer: 2.

A13. The boiling point of water depends on

Solution. Boiling of a liquid occurs at a temperature at which the saturated vapor pressure becomes equal to the external pressure. This means that the boiling point of water depends on atmospheric pressure.

Correct answer: 3.

A14. The figure shows a graph of the melting and crystallization of naphthalene. Which of the points corresponds to the beginning of the solidification of the substance?

Solution. Solidification - the transition from a liquid to a solid state upon cooling. Cooling corresponds to part of the graph 4–7. In the process of solidification, the temperature of the substance remains constant, this corresponds to part of the graph 5-6. Point 5 corresponds to the beginning of solidification of the substance.

Correct answer: 3.

A15. How will the force of the Coulomb interaction of two point motionless charges change if the distance between them is increased by n once?

Solution. The force of the Coulomb interaction of two point immobile charges is equal to

where k - constant, and - the magnitude of the charges, R- the distance between them. If the distance between them is increased to n times, then the force will decrease in times.

Correct answer: 4.

A16. If the cross-sectional area of ​​a homogeneous cylindrical conductor and the electrical voltage at its ends increase by 2 times, then the current flowing through it,

Solution. The current flowing through the conductor is , where U- tension at its ends, R- its resistance, equal to , where ρ is the resistivity of the conductor material, l- its length, S- cross-sectional area. Thus, the current strength is . With a 2-fold increase in the voltage at its ends of the conductor and its cross-sectional area, the current flowing through it increases by 4 times.

Correct answer: 3.

A17. How will the power consumed by an electric lamp change if, without changing it electrical resistance, reduce the voltage on it by 3 times?

Solution. Power consumption is , where U- voltage, R-resistance. With a constant resistance and a decrease in voltage by a factor of 3, the power consumption decreases by a factor of 9.

Correct answer: 2.

A18. What needs to be done in order to change the poles of the magnetic field of a coil with current?

Solution. When the direction of the current in the coil changes, the poles of the magnetic field generated by it change places.

Correct answer: 2.

A19. Will the capacitance of a capacitor change if the charge on its plates is increased by n once?

Solution. The electric capacitance of a capacitor does not depend on the charge on its plates.

Correct answer: 3.

A20. The oscillatory circuit of the radio receiver is tuned to a radio station transmitting on a wave of 100 m. How should the capacitance of the capacitor of the oscillatory circuit be changed so that it is tuned to a wave of 25 m? The inductance of the coil is assumed to be constant.

Solution. The resonant frequency of the oscillatory circuit is equal to

where C- capacitance of the capacitor, L is the inductance of the coil. Contour tuned to wavelength

,

where c is the speed of light. To tune the radio receiver to a four times shorter wavelength, it is necessary to reduce the capacitance of the capacitor by 16 times.

Correct answer: 4.

A21. The camera lens is a converging lens. When photographing an object, it gives an image on film

Solution. When photographing objects that are at a distance greater than the focal length of the lens, a real inverted image is obtained on the film.

Correct answer: 3.

A22. Two cars are moving in the same direction with velocities and relative to the surface of the Earth. The speed of light from the headlights of the first car in the reference frame associated with the other car is

Solution. According to the postulate of the special theory of relativity, the speed of light is the same in all frames of reference and does not depend on the speed of the light source or receiver.

Correct answer: 4.

A23. The figure shows variants of the dependence of the maximum energy of photoelectrons on the energy of photons incident on the photocathode. In which case does the graph correspond to the laws of the photoelectric effect?

Solution. An experimental study of the photoelectric effect has shown that there are frequencies at which the photoelectric effect is not observed. Only for graph 3 there are such frequencies.

Correct answer: 3.

A24. Which of the following statements correctly describes the ability of atoms to emit and absorb energy? isolated atoms can

Solution. Isolated atoms can emit only a certain discrete set of energies and absorb a discrete set of energies less than the ionization energy and any portion of energy that exceeds the ionization energy.

Correct answer: none.

A25. Which of the graphs of the dependence of the number of undecayed nuclei ( N) from time correctly reflects the law of radioactive decay?

Solution. According to the law of conservation of momentum, the speed of the boat will be equal to

Correct answer: 3.

A27. A heat engine with an efficiency of 40% receives 100 J from the heater per cycle. How much heat does the machine give per cycle to the refrigerator?

Solution. The efficiency of the heat engine is . The amount of heat transferred to the refrigerator per cycle is equal to .

Correct answer: 2.

A28. The magnet is removed from the ring as shown in the figure. Which pole of the magnet is closest to the ring?

Solution. The magnetic field created by the induction current inside the ring is directed from right to left. The ring can be thought of as a magnet with the north pole on the left. According to Lenz's rule, this magnet must prevent the removal of the moving magnet and, therefore, attract it. Thus, a moving magnet also has a north pole on the left.

Correct answer: 1.

A29. A lens made of two thin spherical glasses of the same radius, between which there is air (an air lens), was lowered into water (see Fig.). How does this lens work?

Solution. Because the refractive index of air is less than that of water, the air lens is divergent.

Correct answer: 2.

A30. What is the binding energy of the nucleus of the sodium isotope? The mass of the nucleus is 22.9898 amu. e. m. Round your answer to the nearest integer.

Solution. The nucleus of the sodium isotope consists of 11 protons and 12 neutrons. The mass defect is

The binding energy is

Correct answer: 2.

Part B

IN 1. A ball attached to a spring performs harmonic oscillations on a smooth horizontal plane with an amplitude of 10 cm. How far will the ball move from the equilibrium position in the time during which its kinetic energy is halved? Express your answer in centimeters and round to the nearest whole number?

Solution. In the equilibrium position, the system has only kinetic energy, and at maximum deviation - only potential. According to the law of conservation of energy, at the moment when the kinetic energy is halved, the potential energy will also be equal to half the maximum:

.

Where do we get:

.

IN 2. How much heat will be released during isobaric cooling of 80 g of helium from 200 °C to 100 °C? Express your answer in kilojoules (kJ) and round to the nearest whole number?

Solution. Helium is a monatomic gas with a molar mass equal to M= 4 g/mol. 80 g of helium contains 20 mol. The specific heat capacity of helium at constant pressure is . On cooling it will separate

AT 3. Closed conductor resistance R= 3 ohm is in a magnetic field. As a result of changing this field, the magnetic flux penetrating the circuit increased from before . What charge has passed through the cross section of the conductor? Express your answer in millicoulombs (mC).

Solution. When the magnetic flux changes in a closed conductor, an EMF equal to . Under the action of this EMF, current flows in the circuit, and in time Δ t charge passes through the cross section of the conductor

AT 4. Performing the experimental task, the student had to determine the period of the diffraction grating. To this end, he directed a light beam to a diffraction grating through a red light filter, which transmits light with a wavelength of 0.76 microns. The diffraction grating was at a distance of 1 m from the screen. On the screen, the distance between the spectra of the first order turned out to be 15.2 cm. What value of the period of the diffraction grating was obtained by the student? Express your answer in micrometers (µm). (For small angles .)

Solution. Let us denote the distance from the diffraction grating to the screen R= 1 m. Deviation angles are related to the grating constant and the wavelength of light by the equation . For the first order we have:

The distance between the first-order spectra on the screen is

.

AT 5. Determine the energy released during the following reaction: . Express your answer in picojoules (pJ) and round to the nearest integer.

Solution. Using tabular data on the rest energy of the nuclei of the elements involved in the reaction, we determine the released energy:

Part C

C1. A trolley with a mass of 0.8 kg moves by inertia at a speed of 2.5 m/s. A piece of plasticine weighing 0.2 kg falls vertically onto a cart from a height of 50 cm and sticks to it. Calculate the energy that was converted into internal energy during this impact.

Solution. At the moment of impact, the speed of plasticine is equal and directed vertically downwards. This speed was completely extinguished by the reaction force of the support. All the kinetic energy of the fallen piece of plasticine passed into internal energy:

At the moment of sticking a piece of plasticine to the cart, the friction forces equalized the horizontal components of their velocities. Part of the kinetic energy of the trolley has passed into internal energy. Using the law of conservation of momentum, we determine the speed of the cart with plasticine after the collision:

Transferred to internal energy

As a result, the energy that passed into the internal during this impact is equal to

Answer: 1.5 J.

C2. Some helium expands, first adiabatically and then isobarically. The final gas temperature is equal to the initial one. During adiabatic expansion, the gas did work equal to 4.5 kJ. What is the work done by the gas in the whole process?

Solution. Let's depict the processes on the diagram (see Fig.). 1–2 - adiabatic expansion, 2–3 - isobaric expansion. By condition, the temperatures at points 1 and 3 are equal; the work done by the gas in process 1–2 is equal to . Helium is a monatomic gas, so its heat capacity at constant volume is , where ν is the amount of gas substance. Using the first law of thermodynamics for process 1–2, we obtain:

The gas work in process 2–3 can be determined by the formula . Using the Mendeleev-Clapeyron equation and the equality , we get:

The work done by the gas for the entire process is

Answer: 7.5 kJ.

C3. A small charged ball weighing 50 g, having a charge of 1 μC, moves from a height of 0.5 m along an inclined plane with an inclination angle of 30 °. At the top right angle, formed by height and horizontal, there is a fixed charge of 7.4 μC. What is the speed of the ball at the base of the inclined plane if its initial speed is zero? Ignore friction.

Solution. The small ball is in the Earth's gravity field and in the electrostatic field created by the second charge. Both fields are potential, so the law of conservation of energy can be used to determine the speed of the ball. In the initial position, the ball is at a height and at a distance from the second charge. In the final position, the ball is at zero height and at a distance from the second charge. In this way:

Answer: 3.5 m/s.

C4. When a metal is irradiated with light with a wavelength of 245 nm, a photoelectric effect is observed. The work function of an electron from a metal is 2.4 eV. Calculate the amount of voltage that must be applied to the metal in order to reduce the maximum speed of the emitted photoelectrons by a factor of 2.

Solution. The wavelength (λ) of the incident light is related to its frequency (ν) by the equation , where c is the speed of light. Using the Einstein formula for the photoelectric effect, we determine the kinetic energy of photoelectrons:

Work electric field is equal to . The work should be such as to reduce the maximum speed of the emitted photoelectrons by a factor of 2:

Answer: 2 V.

C5. A vacuum diode, in which the anode (positive electrode) and cathode (negative electrode) are parallel plates, operates in a mode where the relationship between current and voltage is satisfied (where a is some constant). By how many times will the force acting on the anode increase due to the impact of electrons if the voltage across the diode is doubled? The initial velocity of the emitted electrons is assumed to be zero.

Solution. When the voltage is doubled, the current will increase by a factor of 1. The number of electrons hitting the anode per unit time will increase by the same factor. At the same time, the work of the electric field in the diode and, as a consequence, the kinetic energy of the colliding electrons will double. The speed of the particles will increase by a factor, the transmitted momentum and the pressure force of individual electrons will increase by the same amount. Thus, the force acting on the anode will increase by times.

Test work on the topic of molecular physics for students in grade 10 with answers. The control work consists of 5 options, each with 8 tasks.

1 option

A1."The distance between neighboring particles of matter is small (they practically touch)." This statement is consistent with the model

1) only solids
2) liquids only
3) solids and liquids
4) gases, liquids and solids

A2. At a constant concentration of particles of an ideal gas, the average kinetic energy of the thermal motion of its molecules increased by 3 times. At the same time, the gas pressure

1) decreased by 3 times
2) increased by 3 times
3) increased 9 times
4) has not changed

A3. What is the average kinetic energy of the chaotic translational motion of ideal gas molecules at a temperature of 27 °C?

1) 6.2 10 -21 J
2) 4.1 10 -21 J
3) 2.8 10 -21 J
4) 0.6 10 -21 J

A4. Which of the graphs shown in the figure corresponds to a process carried out at a constant temperature of the gas?

1) A
2) B
3) B
4) G

A5. At the same temperature, saturated steam in a closed vessel differs from unsaturated steam in the same vessel.

1) pressure
2) the speed of movement of molecules

B1. The figure shows a graph of the change in pressure of an ideal gas as it expands.

What amount of gaseous substance (in moles) is contained in this vessel if the temperature of the gas is 300 K? Round your answer to the nearest whole number.

IN 2. A mixture of two ideal gases, 2 mol each, was kept at room temperature in a vessel of constant volume. Half of the contents of the vessel were released, and then 2 moles of the first gas were added to the vessel. How did the partial pressures of the gases and their total pressure change as a result if the temperature of the gases in the vessel was kept constant? For each position of the first column, select the desired position of the second.

Physical quantities

B) the pressure of the gas in the vessel

Their change

1) increased
2) decreased
3) has not changed

C1. A piston with an area of ​​10 cm 2 can move without friction in a vertical cylindrical vessel, while ensuring its tightness. A vessel with a piston filled with gas rests on the floor of a stationary elevator at an atmospheric pressure of 100 kPa, while the distance from the lower edge of the piston to the bottom of the vessel is 20 cm. see What is the mass of the piston if the change in temperature can be ignored?

Option 2

A1."The distance between neighboring particles of matter is, on average, many times greater than the size of the particles themselves." This statement is consistent

1) only models of the structure of gases
2) only models of the structure of liquids
3) models of the structure of gases and liquids
4) models of the structure of gases, liquids and solids

A2. At a constant concentration of molecules of an ideal gas, the average kinetic energy of the thermal motion of its molecules has changed by 4 times. How did the pressure of the gas change?

1) 16 times
2) 2 times
3) 4 times
4) Hasn't changed

A3.

1) 27 °С
2) 45 °С
3) 300 °С
4) 573 °С

A4. The figure shows graphs of four processes of changing the state of an ideal gas. Isochoric heating is a process

1) A
2) B
3) C
4) D

A5. At the same temperature, saturated water vapor in a closed vessel differs from unsaturated vapor

1) concentration of molecules
2) the average speed of the chaotic movement of molecules
3) average energy of chaotic motion
4) the absence of impurities of foreign gases

B1. Two vessels filled with air at a pressure of 800 kPa and 600 kPa have volumes of 3 or 5 liters, respectively. The vessels are connected by a tube, the volume of which can be neglected in comparison with the volumes of the vessels. Find the pressure established in the vessels. The temperature is constant.

IN 2.

Name

A) the amount of matter
B) the mass of the molecule
C) the number of molecules

1) m/V
2) ν N A
3) m/N A
4) m/M
5) N/V

C1. A piston with an area of ​​10 cm 2 and a mass of 5 kg can move without friction in a vertical cylindrical vessel, while ensuring its tightness. A vessel with a piston filled with gas rests on the floor of a stationary elevator at an atmospheric pressure of 100 kPa, while the distance from the lower edge of the piston to the bottom of the vessel is 20 cm. What will this distance be when the elevator goes down with an acceleration of 3 m / s 2? Ignore changes in gas temperature.

3 option

A1."Particles of matter participate in continuous thermal chaotic motion." This provision of the molecular-kinetic theory of the structure of matter refers to

1) gases
2) liquids
3) gases and liquids
4) gases, liquids and solids

A2. How will the pressure of an ideal monatomic gas change with an increase in the average kinetic energy of the thermal motion of its molecules by 2 times and a decrease in the concentration of molecules by 2 times?

1) will increase by 4 times
2) Decrease by 2 times
3) Decrease by 4 times
4) Will not change

A3. What is the average kinetic energy of the chaotic translational motion of ideal gas molecules at a temperature of 327 °C?

1) 1.2 10 -20 J
2) 6.8 10 -21 J
3) 4.1 10 -21 J
4) 7.5 kJ

A4. On the VT-diagram shows graphs of changes in the state of an ideal gas. The isobaric process corresponds to the graph line

1) A
2) B
3) B
4) G

A5. In a vessel containing only steam and water, the piston is moved so that the pressure remains constant. The temperature at this

1) does not change
2) increases
3) decreases
4) can both decrease and increase

B1. Two vessels with volumes of 40 or 20 liters contain gas at the same temperature but different pressures. After connecting the vessels, a pressure of 1 MPa was established in them. What was the initial pressure in the larger vessel if the initial pressure in the smaller vessel was 600 kPa? The temperature is assumed to be constant.

IN 2. A mixture of two ideal gases, 2 mol each, was kept at room temperature in a vessel of constant volume. Half of the contents of the vessel were released, and then 2 moles of the second gas were added to the vessel. How did the partial pressures of the gases and their total pressure change as a result if the temperature of the gases in the vessel was kept constant?

For each position of the first column, select the desired position of the second.

Physical quantities

BUT) partial pressure first gas
B) partial pressure of the second gas
B) the pressure of the gas in the vessel

Their change

1) increased
2) decreased
3) has not changed

C1. A piston weighing 5 kg can move without friction in a vertical cylindrical vessel, while ensuring its tightness. A vessel with a piston filled with gas rests on the floor of a stationary elevator at an atmospheric pressure of 100 kPa, while the distance from the lower edge of the piston to the bottom of the vessel is 20 cm. When the elevator goes down with an acceleration of 2 m / s 2, the piston will shift by 1.5 see What is the area of ​​the piston if the change in gas temperature is not taken into account?

4 option

A1. In liquids, particles oscillate around their equilibrium position, colliding with neighboring particles. From time to time the particle jumps to another equilibrium position. What property of liquids can be explained by this nature of particle motion?

1) Low compressibility
2) Fluidity
3) Pressure on the bottom of the vessel
4) Change in volume when heated

A2. As a result of the cooling of a monatomic ideal gas, its pressure decreased by 4 times, and the concentration of gas molecules did not change. In this case, the average kinetic energy of the thermal motion of gas molecules

1) decreased by 16 times
2) decreased by 2 times
3) decreased by 4 times
4) has not changed

A3. The average kinetic energy of the translational motion of gas molecules in a balloon is 4.14 10 -21 J. What is the temperature of the gas in this balloon?

1) 200 °С
2) 200 K
3) 300 °С
4) 300K

A4. The figure shows a cycle carried out with an ideal gas. Isobaric heating corresponds to the area

1) AB
2) DA
3) CD
4) BC

A5. With a decrease in the volume of saturated steam at a constant temperature, its pressure

1) increases
2) decreases
3) for some vapors it increases, while for others it decreases
4) does not change

B1. The figure shows a graph of the dependence of gas pressure in a sealed vessel on its temperature.

The volume of the vessel is 0.4 m 3 . How many moles of gas are in this container? Round your answer to the nearest whole number.

IN 2. Match the title physical quantity and the formula by which it can be determined.

Name

A) concentration of molecules
B) the number of molecules
B) the mass of the molecule

1) m/V
2) ν N A
3) m/N A
4) m/M
5) N/V

C1. A piston with an area of ​​15 cm 2 and a mass of 6 kg can move without friction in a vertical cylindrical vessel, while ensuring its tightness. A vessel with a piston filled with gas rests on the floor of a stationary elevator at an atmospheric pressure of 100 kPa. In this case, the distance from the lower edge of the piston to the bottom of the vessel is 20 cm. When the elevator starts moving upward with acceleration, the piston moves 2 cm. With what acceleration does the elevator move if the change in gas temperature can be ignored?

5 option

A1. The least order in the arrangement of particles is typical for

1) gases
2) liquids
3) crystalline bodies
4) amorphous bodies

A2. How will the pressure of an ideal monatomic gas change if the average kinetic energy of the thermal motion of molecules and the concentration are reduced by 2 times?

1) will increase by 4 times
2) Decrease by 2 times
3) Decrease by 4 times
4) Will not change

A3. At what temperature is the average kinetic energy of the translational motion of gas molecules equal to 6.21 10 -21 J?

1) 27 K
2) 45 K
3) 300 K
4) 573 K

A4. The figure shows a cycle carried out with an ideal gas. Isobaric cooling corresponds to the section

1) AB
2) DA
3) CD
4) BC

A5. The vessel under the piston contains only saturated water vapor. How will the pressure in the vessel change if we begin to compress the vapors, keeping the temperature of the vessel constant?

1) The pressure will keep rising
2) The pressure will keep dropping
3) The pressure will remain constant
4) The pressure will stay constant and then start to drop

B1. On the image. shows a graph of the isothermal expansion of hydrogen.

The mass of hydrogen is 40 g. Determine its temperature. The molar mass of hydrogen is 0.002 kg/mol. Round your answer to the nearest whole number.

IN 2. Establish a correspondence between the name of a physical quantity and the formula by which it can be determined.

Name

A) the density of matter
B) the amount of substance
B) the mass of the molecule

1) N/V
2) ν N A
3) m/N A
4) m/M
5) m/V

C1. A piston with an area of ​​10 cm 2 and a mass of 5 kg can move without friction in a vertical cylindrical vessel, while ensuring its tightness. A vessel with a piston filled with gas rests on the floor of a stationary elevator at an atmospheric pressure of 100 kPa, while the distance from the lower edge of the piston to the bottom of the vessel is 20 cm. What will this distance be when the elevator goes up with an acceleration of 2 m / s 2? Ignore changes in gas temperature.

Answers to test on the topic Molecular physics Grade 10
1 option
A1-3
A2-2
A3-1
A4-3
A5-1
IN 1. 20 mol
IN 2. 123
C1. 5.56 kg
Option 2
A1-1
A2-3
A3-1
A4-3
A5-1
IN 1. 675 kPa
IN 2. 432
C1. 22.22 cm
3 option
A1-4
A2-4
A3-1
A4-1
A5-1
IN 1. 1.2 MPa
IN 2. 213
C1. 9.3 cm2
4 option
A1-2
A2-3
A3-2
A4-1
A5-4
IN 1. 16 mol
IN 2. 523
C1. 3.89 m/s 2
5 option
A1-1
A2-3
A3-3
A4-3
A5-3
IN 1. 301 K
IN 2. 543
C1. 18.75 cm

Ideal gas MKT type A Page 9 from 9

MKT IDEAL GAS

BASIC MKT EQUATION , ABSOLUTE TEMPERATURE

At a constant particle concentration, the absolute temperature of an ideal gas was increased by a factor of 4. At the same time, the gas pressure

increased by 4 times

increased by 2 times

decreased by 4 times

hasn't changed

At a constant absolute temperature, the concentration of ideal gas molecules was increased by 4 times. At the same time, the gas pressure

increased by 4 times

increased by 2 times

decreased by 4 times

hasn't changed

The vessel contains a mixture of gases - oxygen and nitrogen - with an equal concentration of molecules. Compare the pressure produced by oxygen ( R to) and nitrogen ( R a) on the walls of the vessel.

1) ratio R to and R a will be different at different temperatures of the gas mixture

2) R to = R a

3) R to > R a

4) R to R a

At a constant concentration of particles of an ideal gas, the average kinetic energy of the thermal motion of its molecules decreased by 4 times. At the same time, the gas pressure

decreased by 16 times

decreased by 2 times

decreased by 4 times

hasn't changed

As a result of the cooling of a monatomic ideal gas, its pressure decreased by 4 times, and the concentration of gas molecules did not change. In this case, the average kinetic energy of the thermal motion of gas molecules

decreased by 16 times

decreased by 2 times

decreased by 4 times

hasn't changed

At constant pressure, the concentration of gas molecules increased by 5 times, and its mass did not change. Average kinetic energy of translational motion of gas molecules

The absolute body temperature is 300 K. On the Celsius scale, it is

1) - 27°C 2) 27°С 3) 300°С 4) 573°С

Temperature solid body dropped by 17°C. On the absolute temperature scale, this change was

1) 290 K 2) 256 K 3) 17 K 4) 0 K

Measuring pressure p, temperature T and concentration of molecules n gas for which ideality conditions are satisfied, we can determine

gravitational constant G

Boltzmann's constantk

Planck's constant h

Rydberg constant R

According to the calculations, the temperature of the liquid should be equal to 143 K. Meanwhile, the thermometer in the vessel shows a temperature of -130 °C. It means that

the thermometer is not designed for low temperatures and needs to be replaced

thermometer shows higher temperature

thermometer shows lower temperature

thermometer shows calculated temperature

At a temperature of 0 °C, the ice of the rink melts. Puddles form on the ice, and the air above it is saturated with water vapor. In which of the media (in ice, in puddles or water vapor) is the average energy of movement of water molecules the highest?

1) in ice 2) in puddles 3) in water vapor 4) everywhere the same

When an ideal gas is heated, its absolute temperature doubles. How did the average kinetic energy of the thermal motion of gas molecules change in this case?

increased 16 times

increased by 4 times

increased by 2 times

hasn't changed

Metal gas cylinders must not be stored at temperatures above a certain temperature, as otherwise they may explode. This is due to the fact that

the internal energy of a gas depends on the temperature

gas pressure depends on temperature

gas volume depends on temperature

Molecules break down into atoms and energy is released

As the temperature of the gas in the sealed vessel decreases, the pressure of the gas decreases. This decrease in pressure is due to the fact that

the energy of thermal motion of gas molecules decreases

the energy of interaction of gas molecules with each other decreases

the randomness of the movement of gas molecules decreases

gas molecules decrease in size as it cools

In a closed vessel, the absolute temperature of an ideal gas decreased by a factor of 3. In this case, the pressure of the gas on the walls of the vessel

The concentration of molecules of a monatomic ideal gas was reduced by a factor of 5. At the same time, the average energy of the chaotic motion of gas molecules was doubled. As a result, the gas pressure in the vessel

decreased by 5 times

increased by 2 times

decreased by 5/2 times

decreased by 5/4 times

As a result of heating the gas, the average kinetic energy of the thermal motion of its molecules increased by 4 times. How did the absolute temperature of the gas change?

increased by 4 times

increased by 2 times

decreased by 4 times

hasn't changed

KLAIPERON-MENDELEEV EQUATION, GAS LAWS

The tank contains 20 kg of nitrogen at a temperature of 300 K and a pressure of 10 5 Pa. What is the volume of the tank?

1) 17.8 m 3 2) 1.8 10 -2 m 3 3) 35.6 m 3 4) 3.6 10 -2 m 3

In a cylinder with a volume of 1.66 m 3 there is 2 kg of nitrogen at a pressure of 10 5 Pa. What is the temperature of this gas?

1) 280°C 2) 140°C 3) 7°С 4) - 3°С

At a temperature of 10 0 C and a pressure of 10 5 Pa, the gas density is 2.5 kg/m 3 . What is the molar mass of the gas?

59 g/mol 2) 69 g/mol 3) 598 kg/mol 4) 5.8 10 -3 kg/mol

A vessel of constant volume contains an ideal gas in an amount of 2 mol. How should the absolute temperature of a vessel with gas be changed when one more mole of gas is added to the vessel so that the gas pressure on the walls of the vessel increases by 3 times?

decrease by 3 times

decrease by 2 times

increase by 2 times

increase 3 times

A vessel of constant volume contains an ideal gas in an amount of 2 mol. How should the absolute temperature of a vessel with gas be changed when 1 mol of gas is released from the vessel so that the pressure of the gas on the walls of the vessel increases by 2 times?

increase by 2 times

increase 4 times

decrease by 2 times

decrease by 4 times

A vessel of constant volume contains an ideal gas in an amount of 1 mol. How should the absolute temperature of a vessel with gas be changed so that when another 1 mole of gas is added to the vessel, the pressure of the gas on the walls of the vessel decreases by 2 times?

increase by 2 times

decrease by 2 times