Question

Compared to the mass and the penetrating power of an alpha particle, a beta particle has(1) less mass and greater penetrating power
(2) less mass and less penetrating power
(3) more mass and greater penetrating power
(4) more mass and less penetrating power

Answer 1

Answer is (1) - less mass and greater penetrating power.

Alpha particle is a ₂⁴He nucleus while beta particles are electrons. Hence, the mass of alpha particle is greater than the mass of beta particle. But, the penetrating power is higher in beta particle than alpha particle. Alpha particles can be blocked by few papers but beta particles can go through those papers.

Answer 2

Answer: A beta particle has less mass and greater penetrating power.

Explanation:

Penetrating power is the power with which a particle travels or pass through a  substance.

Since, it is known that mass of an alpha particle ($^{4}_{2}He$) is more than the mass of a beta particle ($^{0}_{-1}e$). So, a particle that holds less mass can move easily from one place to another.

Therefore, beta particle can move faster as it has only one electron as compared to 2 protons of an alpha particle. Hence, interaction of beta particles is less with the atoms or materials through which it passes.

Therefore, we can conclude that compared to the mass and the penetrating power of an alpha particle, a beta particle has less mass and greater penetrating power.