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प्रश्न
In a cathode ray tube state the purpose of covering cathode by thorium and carbon.
उत्तर
Purpose of covering cathode by thorium and carbon is to reduce its work function, decrease its melting point.
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संबंधित प्रश्न
What is meant by radioactivity?
Give the relative ionizing power of α, β and γ radiations.
In the following fig. shows a radioactive source S in a thick lead container. The radiations pass through an electric field between the plates P and Q. Complete the diagram to show the paths of α , β and γ radiations.
Why is the source S placed in a thick lead container?
A nucleus of an element X which has the symbol `""_84^202` X emits an alpha particle and then a beta particle. The final nucleus is `""_"b"^"a"` Y Find a and b.
Name two radioactive substances.
During the emission of a beta particle, the ______ number remains same.
State any two uses of cathode rays.
Why are materials of low work function preferred as thermionic cathode materials?
Are all the radiations viz. α, β and γ emitted in a single radioactive decay?
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(Take ln 2 = 0.693)
