+7 (727) 344 95 95
Сдать пробный ЕНТ
Русский

Скачай приложение iTest

Готовься к школьным экзаменам в более удобном формате

logo-device logotype logotype-float

Текст 21
Предыдущий конспект Следующий конспект
Конспект

Energy and Electrons

The structure of the atom is similar to planetary system, electrons orbiting around a central nucleus. Electrons also rotate about their own axis. We know the rate of electron rotation and the orbital path determine the amount of energy possessed 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. The atomic bomb and the hydrogen bomb are known to be the example of great amount of energy contained in an atomic structure. There are much simpler methods of changing the amount of energy in a given atomic structure. A photoelectric cell, for example, has a larger area photocathode made from chemically active materials. These materials are known to be alkali metals.

They are electrically active to the degree that they emit electrons when struck by light.

Light falling on the cathode will cause electrons to be emitted; the anode being supplied with a positive potential, electrons will be attracted toward it, producing a photoelectric current. This is well-known as photoemissive cell; it has many uses in modern industry. Basic laws governing the photoelectric effect was studied by Stoletov. They are also true for the laser operations. There are two basic laws of photoelectricity. (A. Kovalenko)



Вопросы

  1. The structure of the atom is similar to_________, electrons orbiting around a central nucleus

  2. The total energy contained in any atom is known to be the sum of the energies of_____________

  3. It is possible to change the atom structure by means of controlled______________

  4. They are electrically active  

  5. Basic laws governing the photoelectric effect was studied by _______

Сообщить об ошибке