question_answer

Define decay constant of a radioactive sample. Which of the following radiations, \[\alpha \]-rays, \[\beta \]-rays, \[\gamma \]-rays (i) are similar to \[\mathbf{X}\] -rays ? (ii) are easily absorbed by matter? (iii) travel with greatest speed? (iv) are similar in nature to cathode rays ?

Answer:

                Decay constant is the reciprocal of the time interval in which the number of active nuclei in a radioactive sample reduces to \[I/e\] times of its initial value. (i) \[\gamma \] -rays are similar to \[\text{X}\] -rays. (ii) \[\alpha \] -rays are easily absorbed by matter. (iii) \[\gamma \] -rays travel with greatest speed. (iv) \[\beta \] -rays are similar to cathode rays.