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प्रश्न
In a cathode ray tube state the purpose of the fluorescent screen.
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उत्तर
Fluorescent screen helps to obtain images on the screen by converting electrical signals to light (or) visual signals by ionizing radiations to light waves.
संबंधित प्रश्न
Represent the change in the nucleus of a radioactive element when a β particle is emitted.
In a cathode ray tube state:
(i) the purpose of covering cathode by thorium and carbon.
(ii) the purpose of the fluorescent screen.
(iii) how is it possible to increase the rate of emission of electrons.
Radioactive substances were found to give off three types of rays. Name them. How do they
(a) React to the magnetic field?
(b) React to the electric field?
(c) Act when different thickness of lead sheets is placed in their path?
Name two radioactive substances.
Justify with reason, whether the following nuclear reactions are allowed or not.
\[\ce{^A_Z X -> ^A_{Z + 1}Y + ^0_{-1}β}\]
Explain, why radium paint, consisting of zinc sulphide and a trace of radium salt, glows in the dark?
Which of the following statements is/are correct?
- α particles are photons
- Penetrating power of γ radiation is very low
- Ionization power is maximum for α rays
- Penetrating power of γ radiation is very high
88Ra226 experiences three α - decay. Find the number of neutrons in the daughter element.
The mean lives of a radioactive substance are 1620 and 405 years for β-emission and β-emission respectively. The time after which three fourth of a sample will decay if it is decaying both by β-emission and β-emission simultaneously will be ______ years.
(Take ln 2 = 0.693)
In the following atoms, which one is a radioisotope? Give one use of this isotope.
O16, C14, N14, He4
