Physics [1 Mark Question Answer]

This reaction is allowed because, the mass number as well as atomic number are conserved here.

The ionising power of α-radiation is nearly 100 times that of β radiations and nearly 10,000 times that of γ-radiations.

γ -radiations are nearly 100 times more penetrating than β-radiations and 10,000 times more penetrating than α-radiations.

The number of protons in the nucleus is known as the atomic number of the element and is denoted by Z.

Process of spontaneous emission of α or β and γ radiations from the nuclei of atoms during their decay.

Hot cathode ray tube is used in T.V.

Cathode rays are used for:
(i) Converting electrical signal into a visual signal, (ii) In television.

When a cathode ray beam strikes a zinc sulphide screen, a bright spot is seen on the screen.

A cathode ray beam while passing through an .electric field is deflected towards the positive plate (i.e. towards higher potential).

Two properties are:
(i) High melting point. (ii) Low work function.

Neutrons and protons are collectively called nucleons.

Nucleus: The central core of an atom is called nucleus. The nucleus contains protons and neutrons.

No change. Since the phenomenon of radioactivity is not due to the orbital electrons which would be easily affected by such changes. Radioactivity is the property of the nucleus.

Particle emitted is β-particle.

A large amount of heat is produced when the high kinetic energy electrons strike the target. Therefore it is necessary to cool the tube.

The material of the target C is “tungsten.”

Radiation B is called “X-rays”.

‘Electrons’. The phenomenon of emission of these particles is called “thermionic emission”.