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The blue colour of the sky is due to the scattering of light. Which phenomenon is responsible for the red colour of the sun at sunrise and sunset?
Dispersion
Refraction
Scattering
Reflection
Scattering
The red colour of the sun at sunrise and sunset is primarily due to the scattering of light by atmospheric particles. During these times, sunlight travels through a thicker layer of the Earth's atmosphere, causing shorter wavelengths (blue/violet) to scatter away and allowing longer wavelengths (red/orange) to reach the observer.
The red colour of the sun at sunrise and sunset is primarily due to the scattering of light by atmospheric particles. During these times, sunlight travels through a thicker layer of the Earth's atmosphere, causing shorter wavelengths (blue/violet) to scatter away and allowing longer wavelengths (red/orange) to reach the observer.
Think of the atmosphere like a filter; it captures the 'smaller' blue colors passing through it, while the 'larger' red colors are strong enough to push through the long distance to reach your eyes.
B-S-R: Blue Scatters, Red Remains.
IтИЭ╬╗41тАЛ тАФ Rayleigh scattering intensity law where I is intensity and ╬╗ is wavelength.
According to Rayleigh's law of scattering, the intensity of scattered light I is inversely proportional to the fourth power of its wavelength, i.e., IтИЭ╬╗41тАЛ. Since blue light has a shorter wavelength, it is scattered more efficiently. At sunrise and sunset, light travels a longer path through the atmosphere, meaning most blue light is removed by scattering before reaching the eyes, leaving the longer-wavelength red light dominant.
Light with longer wavelengths undergoes less scattering.
The path length of sunlight is maximum at the horizon (sunrise/sunset) and minimum at noon.
Rayleigh scattering is valid for particles with size dтЙк╬╗.
Red color of danger signals
Visibility of sunset hues
At noon, the sun appears white because light travels a shorter distance and scattering is minimal.
Option A (Dispersion) refers to the splitting of white light into its constituent colors (e.g., prism).
Option B (Refraction) refers to the bending of light at the interface of two media.
Option D (Reflection) refers to the bouncing back of light from a surface.
C is correct тАФ The red colour of the sun at sunrise and sunset is a result of the scattering of shorter wavelength light by atmospheric molecules, leaving mostly longer red wavelengths to reach our eyes.
Always remember that 'Scattering' relates to the change in direction of light due to particles, whereas 'Dispersion' is specific to the separation of colors based on refractive index.