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Alexei Leonov was the first man to step into space.
To build new electric stations is to develop our industry.
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ENERGY AND ELECTRONS
The structure of atom is similar to planetary system, electrons orbiting around a certain nucleus. Electrons also rotate about their own axes. We know the rate of electron rotation and the orbital path determine the amount of energy passed by the atom.
The total energy contained in any atom is known to be the sum of the energies of the individual electrons. Electrons of a given atom can be changed from their position by different energies. Radioactive materials, for example, are constantly undergoing a change. Radioactive energy emitted from the material changes it from one form to another. It is also possible to change the atom structure by means of controlled nuclear reaction.
There is a simple method of changing the amount of energy in a given atomic structure. A photoelectric cell has a large area photocathode made from chemically active materials. These materials are alkali metals.
There are two basic laws of photo electricity. The first law states that the number of electrons released per unit of time from photoelectric surface is directly proportional to the intensity of the incident light ( падающий свет ).
The second law states that the maximum energy of electrons coming from photoelectric surface is independent of the intensity of the incident light and is directly proportional to the frequency of the light. The higher the frequency of incident of radiation, the higher is the energy of photoelectrons.