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Stamps dedicated to international geophysical scientific programs

Алтыкис А. В.

Rough automatic draft, low quality: expect mistakes and awkward wording. It will be replaced by a better translation. Original →

STAMPS DEDICATED TO INTERNATIONAL GEOPHYSICAL SCIENTIFIC PROGRAMS

Geophysics - the science of physical processes occurring on Earth - also includes the study of various phenomena observed in various layers of the atmosphere, in the water shell, the solid crust and the interior of our planet. Geophysical phenomena often span most or all of the globe. Therefore, even at the dawn of the development of geophysics, it became clear that it was necessary to pool the efforts of scientists from different countries to conduct research according to a single program in different parts of the globe.

In October 1951, the International Council of Scientific Unions decided to hold an International Geophysical Year. From July 1, 1957 to December 31, 1958, scientists from many countries, under a special program, carried out a huge amount of coordinated research in all regions of the globe. The International Geophysical Year was the largest scientific event in which more than 50 thousand scientists from 60 countries took part.

The newest and most difficult task at this time is the launch of artificial Earth satellites. Therefore, the emblem of the International Geophysical Year depicts a globe with an artificial satellite flowing around it.

The Soviet Union issued three series of stamps dedicated to the International Geophysical Year.

They reflect the most important research that was carried out in the USSR under the international program. One of the stamps of the first series (issued in 1957) depicts a chromospheric-photospheric telephone for studying solar activity, another shows an observatory and a radiar installation for observing meteorites, and the third shows launch packages for studying the upper layers of the atmosphere.

The second series (issued in 1958) is devoted to the study of geomagnetism, auroras and meteorology.

In the third series you see a stamp with an image of the Soviet research vessel “Vityaz”, studying various phenomena in the oceans (at the top of the stamp the route of the “Vityaz” in the Indian Ocean is shown), a stamp dedicated to glasiology (the study of the Earth’s ice cover), as well as a stamp dedicated to Antarctica with a diagram of the location of Soviet Antarctic stations. In the same series a stamp was issued dedicated to batch research. All four stamps feature the International Geophysical Year emblem.

A. V. Altykis

71

To problem M84

It is natural to imagine a project prim, an additional infinite point at a distance, as a circle (when point X runs through the prim, then X’ goes through a full revolution around the circle).

If point X moves in one direction, then Y=f(X) moves in the opposite direction, therefore the mapping f has two fixed points Z₁ and Z₂ such that f(Z₁)=Z₁; f(Z₂)=Z₂.
(This is true for any continuous one-to-one mapping f of a circle onto itself, changing the direction of the traversal.

If point L is an infinite distant point of line l, then it is easy to check that f(f(L))=L, and f(L)≠L. The mapping X−f(f(X)) is projective and has three fixed points: Z₁, Z₂ and L, so f(f(X))=X for all X.

To the article “Pyramid and Sphere”

  1. a8(6±1)\frac{a}{8} (\sqrt{6} \pm 1).
  2. (56+22)R(5\sqrt{6} + \sqrt{22})R.
  3. a23⋅4.1+73⋅5.52\frac{a}{2\sqrt{3}} \cdot 4. 1 + \sqrt{\frac{7}{3}} \cdot 5. \frac{\sqrt{5}}{2} see
  4. 368a.7.31716b2\frac{3\sqrt{6}}{8} a. 7. \frac{3\sqrt{17}}{16} b^2.

To “Entrance exam option”

MOSCOW STATE UNIVERSITY named after M. V. LOMONOSOV

Department of the Economic Library of the Faculty of Economics

  1. 6 parts of the first type and 10 parts of the second type.

Note. If the number of produced parts of the first and second type is denoted by x and y, respectively, then 3x+5y=68. If parts of the first type were made of M₁ metal, then each oar part would be 1.6/x kkey, and if made of M₂ metal, then 5.2/x kkey. Since in fact each part of the first type weighs 0.31 kkey and is made from an alloy of metals M₁ and M₂, then 1.6/x<0.31<5.2/x (why?), that is, 5531\frac{5}{31}<x<162431\frac{24}{31}. Similarly, we obtain that 81417\frac{14}{17}<y<13417\frac{4}{17}. Thus, the problem comes down to finding integer values ​​of x and y that satisfy the equation

mu at n≥6n \geq 6 the total term ana_n of the sequence as the sum of two increasing expressions will increase with increasing number nn. Consequently, the smallest term of the sequence must be sought among the terms a1,a2,a3,a4,a5,a6a_1, a_2, a_3, a_4, a_5, a_6. This can be done simply by brute force.

  1. ρ2−(R−r)24(R+r)2.\frac{\rho^2 - (R - r)^2}{4(\sqrt{R} + \sqrt{r})^2}.

Direction e. Prove that the center of the required ball lies in a plane passing through the center of the given ball and perpendicular to the axis of the cylinder.

  1. 648 numbers.

Department of Political Economy, Faculty of Economics

  1. 17%.
  2. −V5+12<x<1,x>5+12.\frac{-V\sqrt{5}+1}{2} < x < 1, x > \frac{\sqrt{5}+1}{2}.
  3. 5π6+2kπ≤x≤13π6+2kπ,\frac{5\pi}{6} + 2k\pi \leq x \leq \frac{13\pi}{6} + 2k\pi,
    k=0,±1,±2,…k = 0, \pm 1, \pm 2, \dots
  4. 22−122+1R и 22+122−1R.\frac{2\sqrt{2}-1}{2\sqrt{2}+1}R \text{ и } \frac{2\sqrt{2}+1}{2\sqrt{2}-1}R.

Direction e: Note that there are two balls that satisfy the requirements of the problem.

Department of biological biology faculty

  1. x=−3x = -3. 2. π14:12\pi\sqrt{14}:12. 3. 4e/cm34e/cm^3.
  2. x≠(−1)n+1π9+nπ3x \neq (-1)^{n+1}\frac{\pi}{9} + \frac{n\pi}{3}, where nn is any integer. 5. 3:1. Direction e. Let p1,p2p_1, p_2 be the perimeters of triangles ABEABE and ECDECD, respectively, and ⇒BAE=α\Rightarrow BAE = \alpha. Show that p1:p2=(1−sin⁡α2):cos⁡αp_1:p_2 = \left(1 - \sin \frac{\alpha}{2}\right):\cos \alpha. Set the data to sin⁡α2=23\sin \frac{\alpha}{2} = \frac{2}{3}.

Faculty of Geography

  1. 16 parts. 2. a+ba+b.
  2. x1=π2+kπ,x2=(−1)nπ6+nπx_1 = \frac{\pi}{2} + k\pi, x_2 = (-1)^n\frac{\pi}{6} + n\pi, where kk and nn are any integers. 4. AE:EB=4:3AE:EB = 4:3. Direction e: Prove that ⇒ABC=90∘\Rightarrow ABC = 90^\circ. Next, use the theorem: the square of a tangent is equal to the product of a secant and its outer part. 5. 3<x<103 < x < 10.

MOSCOW AUTOMOBILE AND ROAD INSTITUTE

Option 1

  1. 15 ∂m2\partial m^2. 3. x=1/12x = 1/12. 4. x1=π2+kπx_1 = \frac{\pi}{2} + k\pi; x2,3=±π3+kπx_{2,3} = \pm \frac{\pi}{3} + k\pi. 5.5 cm.

Option 2

          1. 1/3; 9. 4. x=±2π9+23πkx = \pm \frac{2\pi}{9} + \frac{2}{3}\pi k. 5. 25 π\pi.

To note «Kvant» for younger students

(see «Kvant» No. 1, 3rd cover page)

  1. It is clear that if the cork is turned so that a person must press the key from top to bottom, then the maximum force with which he can press on the key is equal to his weight. However, in the case where the key must go from the floor upward, this force can be significantly greater than the weight: a strong person can easily lift a load significantly exceeding his own weight.
  2. 24-manungi.
  3. Light bulbs of the same power must be connected in parallel to each other and then the resulting two groups of light bulbs must be connected in series.
  4. 24 days.
  5. A duck’s feet are wider apart than a chicken’s. Therefore, its center of gravity is located from the fulcrum, and during the step, which is the same for the duck and the chicken, the duck turns at a larger angle than the chicken: large moments of force of the gravity relative to the fulcrum, and therefore greater acceleration and angular velocity of rotation.
  6. Brick has greater thermal conductivity than wood. When swaddled, the surface of a wooden wall quickly becomes warm. A brick wall that has “accumulated cold” transfers it to the outside, and its temperature is below 0°C, that is, below the ambient air temperature.