Arrange the following radiations in order of increasing ionization of air.

I. Alpha

Il. Gamma

IIl. Beta

A. I < III < II
B. II < I < III
C. II < III < I
D. I < II

Correct Answer:

Option C – II < III < I

Explanation

Alpha particles are highly ionising because of their double positive charge, large mass (compared to a beta particle) and because they are relatively slow.

They can cause multiple ionisations within a very small distance.

And the gamma radiation has the least ionising power.