Scattering Wavelength Dependence in Atmosphere

Atmospheric scattering describes how light interacts with particles in the air. The way scattering depends on the light's wavelength ($\lambda$) differentiates various types:

Analyzing Scattering Types:

• Rayleigh Scattering: Occurs when particles (like air molecules) are much smaller than the light's wavelength (e.g., $d \lt 0.1\lambda$). Its intensity is highly dependent on wavelength, varying with $1/\lambda^4$. This causes blue light to scatter more than red light.
• Mie Scattering: Happens when particles (like aerosols or dust) are similar in size to the wavelength (e.g., $0.1\lambda \lesssim d \lesssim 10\lambda$). This scattering is less dependent on wavelength than Rayleigh scattering, but it still shows some variation.
• Non-Selective Scattering: Occurs when particles (like large water droplets in clouds) are much larger than the light's wavelength (e.g., $d \gt 10\lambda$). In this case, the scattering is approximately the same for all visible wavelengths, making it effectively independent of wavelength.

Identifying Wavelength-Independent Scattering

The question requires identifying the scattering type that is not dependent on wavelength in the visible region.

• Rayleigh scattering (a) is strongly wavelength-dependent.
• Mie scattering (b) exhibits some wavelength dependence.
• Non-Selective scattering (c) is considered wavelength-independent.

Therefore, Non-Selective scattering is the correct answer.

The correct option is (c) only.