Consider alpha particle , `beta` particle and `gamma - rays` , each having an energy of `0.5 MeV` . In increase order of panetrating power , the radiation are .

Options

A. (a) `alpha, beta, gamma`
B. (b) `alpha, gamma, beta`
C. (c) `beta, gamma, alpha`
D. (d) `gamma, beta, alpha`

Explanation

To determine the order of penetrating power for alpha particles, beta particles, and gamma rays, we can analyze their properties based on their mass and charge.

### Step-by-Step Solution:

1. **Identify the Types of Radiation**:
- Alpha particles (α): These are helium nuclei consisting of 2 protons and 2 neutrons. They have a positive charge and a relatively large mass.
- Beta particles (β): These are high-energy, high-speed electrons (β-) or positrons (β+). They have a small mass and a negative (or positive) charge.
- Gamma rays (γ): These are electromagnetic radiation with no mass and no charge.

2. **Understand the Concept of Penetrating Power**:
- Penetrating power refers to the ability of radiation to pass through materials. It is influenced by the mass, charge, and energy of the particles.

3. **Analyze the Penetrating Power**:
- **Alpha particles**: Due to their larger mass and positive charge, alpha particles interact strongly with matter. They have the least penetrating power and can be stopped by a sheet of paper or a few centimeters of air.
- **Beta particles**: Beta particles are lighter and have a smaller charge compared to alpha particles. They can penetrate further than alpha particles but are still stopped by a few millimeters of plastic or glass.
- **Gamma rays**: Gamma rays, having no mass and no charge, can penetrate materials much more effectively than both alpha and beta particles. They require dense materials like lead or several centimeters of concrete to be significantly attenuated.

4. **Order the Radiation by Penetrating Power**:
- Based on the analysis, we can arrange the types of radiation in increasing order of penetrating power:
- Alpha particles (least penetrating)
- Beta particles (moderate penetrating)
- Gamma rays (most penetrating)

### Final Order:
- **Increasing order of penetrating power**:
- Alpha particles < Beta particles < Gamma rays