Answer: The order of penetrating power from greatest to least is gamma ray, beta particle, alpha particle.
Explanation:
Penetration power is defined as the movement of particles or the ray through an object. It is directly proportional to the energy of the particle.
\(\text{Energy of the particle}\propto \text{Penetrating power}\)
So, more is the energy of a particle, more will be its penetrating power.
We know that:
Gamma rays have the highest energy, followed by beta particle and then by alpha particle.
Thus, the ascending order of the penetration power of alpha rays, beta rays, and gamma rays will be:
Alpha rays < Beta rays < Gamma rays
Hence, the order of penetrating power from greatest to least is gamma ray, beta particle, alpha particle.
