Advertisements
Advertisements
प्रश्न
In a cathode ray tube state. How is it possible to increase the rate of emission of electrons.
Advertisements
उत्तर
(i) Decrease work function.
(ii) Coating the cathode with a layer of alkaline earth metallic oxides (or) hydrides.
APPEARS IN
संबंधित प्रश्न
State three factors on which the rate of emission of electrons from a metal surface depends
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.
A certain nucleus A (mass number 238 and atomic number 92) is radioactive and becomes a nucleus B (mass number 234 and atomic number 90) by the loss of one particle.
What particle was emitted?
Justify with reason, whether the following nuclear reactions are allowed or not.
\[\ce{^A_Z X -> ^A_{Z - 2}X + ^4_{2}He}\]
An electrons emitter must have how much work function and melting point.
Two radioactive nuclei are represented by xAp and yAq and when p and q are mass numbers and x, y are the atomic number. How can the products be represented, i .e., what are the new values of p, q. x and y after the emission of an α-particle and a β-particle from A and B respectively.
From α, β and γ-rays, name the one which is not affected by electric or magnetic field?
Two radioactive materials A and B have decay constants 25λ and 16λ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of B to that of A will be "e" after a time `1/("a"lambda)` The value of a ______.
