Which of the following electromagnetic waves has smaller wavelength ?

Options

A. X-rays
B. Microwaves
C. `gamma`-rays
D. Radiowaves.

Answer

To determine which electromagnetic wave has the smallest wavelength, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Electromagnetic Spectrum**: The electromagnetic spectrum is a range of all types of electromagnetic radiation, which includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

2. **Identify the Order of Wavelengths**: The electromagnetic spectrum is arranged in order of decreasing wavelength:
- Radio Waves: ~1 meter (longest wavelength)
- Microwaves: shorter than radio waves
- Infrared: shorter than microwaves
- Visible Light: shorter than infrared
- Ultraviolet: shorter than visible light
- X-rays: shorter than ultraviolet
- Gamma Rays: ~10^-12 meters (shortest wavelength)

3. **Determine the Wavelengths**: From the information above, we can see that as we move from radio waves to gamma rays, the wavelength decreases. Gamma rays have the smallest wavelength in the electromagnetic spectrum.

4. **Conclusion**: Based on the order of the electromagnetic spectrum, gamma rays have the smallest wavelength compared to all other types of electromagnetic waves.

5. **Final Answer**: Therefore, the electromagnetic wave with the smallest wavelength is **gamma rays**.