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.
RELATED QUESTIONS
What are free electrons?
What happens if the negative potential is changed on a grid?
Complete the diagram as given above by drawing the deflection of radioactive radiations in an electric field
In following fig. shows a mixed source S of alpha and beta particles in a thick lead container. The particles pass through a magnetic field in a direction perpendicular to the plane of paper (inwards as shown by x). State and show in the diagram how the particles get affected.
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 a common device where a hot cathode ray tube is used.
What is meant by Radioactivity?
What is the value of the speed of gamma radiations in air or vacuum?
Mention one important function of ear main parts:
State the principle on which the functioning of a nuclear reactor is based.
In U238 ore containing Uranium the ratio of U234 to Pb206 nuclei is 3. Assuming that all the lead present in the ore is final stable product of U238. Half life of U238 to be 4.5 × 109 years and the age of ore is ______ × 109 years. (in 109 years)
