Correspondence School of Physics and Technology at MIPT

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Correspondence School of Physics and Technology at MIPT

The Correspondence Physics and Technology School (3FTSH) at the Moscow Order of Labor Red Replacement Physics and Technology Institute (MIPT) is enrolling students from educational institutions and secondary schools located on the territory of the RSFSR in grades 8, 9 and 10 for the 1989/90 academic year.

The goal of the school is to help students study independently to deepen their knowledge of physics and mathematics. When admitting to 3FTS, preference is given to students living in rural areas and workers’ settlements, where such assistance is especially needed.

School education is free.

In addition to individual students, 3FTS accepts physics and technology circles, which can be organized in any secondary school by two teachers - physics and mathematics. The leaders of the circles recruit and enroll students (at least 8-10 people) who have successfully completed the introductory task of 3FTS. A circle is accepted into the 3FTSH if the director of the schoolOLS informs the 3FTSH of the names, having, in the absence of circle leaders and premises, a list of circle members (indicating the class in the 1989/90 academic year and the final grades for introductory assignments in physics and mathematics). All materials on organizing circles and an envelope for a response about accepting a circle in 3FTSH with a return address to

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The name of one of the leaders of the circle should be sent to the address of 3FTSH (141700 Dolgoprudny, Moscow region, MIPT, 3FTSH with the indication “Circle”) before May 25, 1989. (Notebooks with the work of members of the circle are not sent to 3FTSH). The work of the directors of correspondence physics and mathematics circles can be paid for by schools at the request of the 3FTS at MIPT as elective classes.

Students of 3FTS and heads of physics and technology clubs will receive tasks in physics and mathematics in accordance with the 3FTS program, as well as solutions to these tasks recommended by 3FTS. The assignments contain theoretical material and analysis of typical problems and examples on the topic, as well as 10-14 assignments for independent solution. These are both simple tasks and more complex ones (at the level of competitive tasks at MIPT). The work of correspondence students is checked in the 3FTS and its filps, members of the circle - its leaders.

Moscow students are given classes in physics and mathematics twice a week according to the 3FTS program in evening advisory centers (in a number of Moscow schools), admission to which is carried out either based on the results of the 3FTS introductory task, or based on a final interview in physics and mathematics (inquiries by phone 408-51-45).

Each student completes the introductory assignment in physics and mathematics independently. The work needs to be carefully transcribed (in Russian) into one school area.

The order of tasks should be the same as in the assignment. Send the notebook in a large envelope with a simple parcel (just do not roll it into a tube). Along with your decision, be sure to send a certificate from the school you are attending, indicating your class. Place the certificate on the inside cover of your notebook. Without this certificate, the decision will be considered. It is placed on the outside cover according to the sample (all surnames, first names and absences in this form must be written clearly, in block letters, in the nominative case). Below, under the completed form, draw a table for grades for the introductory task.

1. Region (region or ASSR)
2. Last name, first name, patronymic
3. Class
4. School number and telephone number
5. Last name, first name, patronymic of your physics teacher
   in mathematics
6. Profession parent and position father
   mother
7. Detailed home address

Ulyanovsk region
Andreev Nikolay Vladimirovich selmoy
school No. 25, t. 3-32-17
Emelyanova Olga Aleksadrovna
Kuzmin Boris Romanovich
telephone cook
433510 Dmitrovgrad, Ulyanovsk region, st. Lenina, 3, apt. 14.

To receive an answer to the introductory task, please fill your notebook with an envelope on which you write your home address.
Deadline for sending the decision

bots at the address: 198904 Old Peterf, st. May 1, 100, Leningrad State University, Leningrad branch of the 3FTS at MIPT.
Teachers of Amurskaya,

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Introductory task
Physics

1. Two ships are moving towards each other. The speed of one ship is $v_1$, the other is $v_2$. When the distance between the ships becomes $s$, a dove takes off from one of the ships and flies to the other ship. Accessible by him, he turns sharply and flies back, etc. The pigeon flies between ships at a practical constant speed of $v$. How far will he fly until the ships meet?

2. A pedestrian walked from one city to another. When he had walked 27 km, an automatic vehicle drove out to everyone, having a speed 10 times faster than a pedestrian. They reached the second city at the same time. What is the distance between cities?

3. 4 liters of water were poured into a cylindrical vessel with a bottom area of ​​200 cm² and a height of 30 cm. A rod with a cross-section of 100 cm², the height of which is equal to the height of the vessel, is lowered into the vessel. What minimum mass must the rod have in order for it to sink to the bottom of the vessel?

4. A piece of ice with volume $V$ floats into a vessel with water, inside of which there is a piece of lead with volume $v$. How will the water level in the vessel change as the ice grows? The density of water is $1 \text{ г/cm}^3$, ice - 0.9 g/cm³, lead - 11.3 g/cm³.

5. A thermos contains equal masses of water and ice at a temperature of 0 °C. Water is poured into a thermos, the mass of which is equal to the total mass of water and ice initially found in the thermos, and the temperature is 49.9 °C. What temperature is set in the thermos? The specific heat of water is 4200 J/(kg °C), the specific heat of melting of ice is 335 kJ/kg.

6. When making ice in the refrigerator, it took 5 minutes to cool the water from 4°C to 0°C and another 1 hour 40 minutes to turn it into ice. Define

from these data, the specific heat of fusion of ice. The specific heat of water is 4200 J/(kg °C).

7. Two balls are thrown simultaneously at each other at the same speed: one vertically upward with the surfaces of the earth, the other vertically downward from a height of $H$. Find these speeds if it is known that by the time of the meeting one of the balls has traveled the distance $H/3$.

8. The radius of the Sun is 108 times the radius of the Earth, and the density of the Sun is 0.25 the density of the Earth. Find the acceleration of gravity at the surface of the Sun.

9. An electric kettle has two windings. When one winding is turned on, the kettle boils after 10 minutes, when the other winding is turned on, after 15 minutes. How long will it take the kettle to boil if the windings are turned on: a) in parallel? b) sequentially?

10. The body slides down an inclined plane with an angle of inclination of 30°, and then along a horizontal plane. Having passed along a horizontal plane a distance equal to the length of the inclined plane, the body stopped. Find the coefficient of friction.

11. An atom at rest breaks up into two parts, the masses of which are $m_1$ and $m_2$, and the total kinetic energy is $E$. Determine their speeds.

12. A certain amount of gas is heated from a temperature of 300 K to a temperature of 400 K. In this case, the volume of the gas changes in proportion to the temperature. The initial gas volume is 3 liters. The pressure changed at the end of the process turns out to be 1 atm. How much work was done by the gas in this process?

13. A load suspended on a thread of length $l$ rotates uniformly in a circle in a horizontal plane. Find the period of rotation of the load if, during its rotation, the thread deviates from the vertical by an angle $a$.