Which of the following radiation has the least wavelength?

Options

A. `gamma`-ray
B. X-ray
C. Infrared
D. Radio waves

Answer

To determine which radiation has the least wavelength among the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Electromagnetic Spectrum**: The electromagnetic spectrum consists of various types of radiation arranged in order of increasing frequency and decreasing wavelength. The order is as follows:
- Radio Waves
- Microwaves
- Infrared
- Visible Light
- Ultraviolet (UV)
- X-rays
- Gamma Rays
- Cosmic Rays

2. **Identify the Relationship Between Wavelength, Frequency, and Energy**:
- The energy (E) of electromagnetic radiation is related to its frequency (ν) by the equation:
\[ E = hν \]
where \( h \) is Planck's constant.
- The wavelength (λ) is related to frequency and energy by the equation:
\[ E = \frac{hc}{λ} \]
where \( c \) is the speed of light.
- From these equations, we can deduce that energy is directly proportional to frequency and inversely proportional to wavelength. This means that as frequency increases, wavelength decreases.

3. **Analyze the Given Options**:
- We need to compare the wavelengths of the following types of radiation:
- Gamma Rays
- X-rays
- Infrared
- Radio Waves

4. **Determine the Wavelength Ranges**:
- Radio Waves: Approximately \( 10^3 \) meters (longest wavelength)
- Infrared: Approximately \( 10^{-5} \) meters
- X-rays: Approximately \( 10^{-10} \) meters
- Gamma Rays: Approximately \( 10^{-12} \) meters (shortest wavelength)

5. **Identify the Radiation with the Least Wavelength**:
- From the wavelength ranges, we can see that Gamma Rays have the shortest wavelength, which is approximately \( 10^{-12} \) meters.

6. **Conclusion**:
- Therefore, the radiation with the least wavelength among the options provided is **Gamma Rays**.

### Final Answer:
The radiation with the least wavelength is **Gamma Rays**.

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