Question

Which is having minimum wavelength : -

• A. X-rays
• B. Ultra violet rays
• C. $\gamma$-rays
• D. Cosmic rays

Answer 1

The Correct Option is D

To determine which type of radiation has the minimum wavelength among the given options, we need to understand the electromagnetic spectrum and the typical wavelengths of different types of radiation.

The electromagnetic spectrum includes different types of radiation arranged according to their wavelength or frequency. Here's the general order from longest wavelength to shortest wavelength (highest frequency):

• Radio Waves
• Microwaves
• Infrared
• Visible Light
• Ultraviolet Rays
• X-Rays
• Gamma Rays (\gamma-rays)
• Cosmic Rays

Now, let us examine the wavelengths of the given options:

1. X-rays: Typically have wavelengths ranging from about \(0.01\) to \(10\) nanometers (nm).
2. Ultraviolet rays: Wavelengths generally range from \(10\) nm to \(400\) nm.
3. \gamma-rays: These have shorter wavelengths than X-rays, generally less than \(0.01\) nm.
4. Cosmic rays: These are subatomic particles, primarily protons, that travel through space at high energy levels and can have wavelengths less than that of gamma rays, even approaching the order of \(10^{-15}\) meters or smaller.

Based on the analysis, Cosmic rays indeed have the minimum wavelength among the options listed, often shorter than \( \gamma \)-rays and X-rays. This is due to their extremely high energy levels and smaller wavelengths.

Therefore, the correct answer is Cosmic rays.