Advertisements
Advertisements
Question
State two properties that a substance should possess when used as a thermionic emitter.
Advertisements
Solution
Two properties are:
(i) High melting point. (ii) Low work function.
APPEARS IN
RELATED QUESTIONS
A radioactive substance is oxidized. Will there be any change in the nature its radioactivity? Give a reason for your answer
What is thermionic emission?
A nucleus `""_11^24Na` emits a beta particle to change into Magnesium (Mg)
(i) Write the symbolic equation for the process.
(ii) What are numbers 24 and 11 called?
(iii) What is the general name of `""_12^24Mg `with respect to `""_11^24Na` ?
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?
Name two radioactive substances.
A nucleus is \[\ce{^24_11 Na}\] β-radioactive.
Write the equation represent β-decay.
In a cathode ray tube state. How is it possible to increase the rate of emission of electrons.
What is meant by Radioactivity?
