Which rays are not the portion of electro-magnetic spectrum?

Options

A. x-rays
B. microwaves
C. `alpha`-rays
D. radiowaves.

Answer

**Step-by-Step Solution:**

1. **Understand the Electromagnetic Spectrum:**
The electromagnetic spectrum consists of various types of electromagnetic radiation arranged in order of increasing frequency and decreasing wavelength. The main categories include gamma rays, X-rays, ultraviolet (UV) rays, visible light, infrared (IR) rays, microwaves, and radio waves.

2. **Identify the Types of Rays in the Spectrum:**
- Gamma rays
- X-rays
- Ultraviolet (UV) rays
- Visible light
- Infrared (IR) rays
- Microwaves
- Radio waves

3. **Determine Which Rays Are Not Included:**
To answer the question, we need to identify any rays that are commonly known but do not belong to the electromagnetic spectrum.

4. **Analyze Common Rays:**
- Alpha rays (α-rays) are not part of the electromagnetic spectrum; they are a type of particle radiation consisting of helium nuclei emitted by some radioactive materials.
- Other rays such as beta rays (β-rays) and gamma rays (γ-rays) are also not part of the electromagnetic spectrum in the same way as the other listed types.

5. **Conclude the Answer:**
Since alpha rays are not included in the electromagnetic spectrum, the answer to the question is that alpha rays are not part of the electromagnetic spectrum.

**Final Answer:**
Alpha rays are not a portion of the electromagnetic spectrum.

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