The sun looks reddish at the time of sunrise and sunset.
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At the time of sunrise and sunset, the sun is near the horizon. The sun rays have to travel a larger part of atmosphere to reach the observer. As `I_(s) prop (1)/(lambda_(4))` and `lambda_(r )` is largest in the visible region, red colour is scattered the least, and enters our eyes.
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With the help of a labelled diagram, explain why the sun appears reddish at the sunrise and the sunset.
(a) Give reasons for the following: (i) The sky appears to be blue during day time to a person on earth. (ii) The sky near the horizon appears to have a reddish hue at the time of sunset and sunrise. (iii) The sky appears dark instead of blue to an astronaut. (iv) The stars appear to twinkle. (v) The planets do not twinkle.
Why the sun looks red at the time of setting ?
The red colour of the sun at the time of sunrise and sunset is because :
Assertion : Sun looks reddish at sunrise and sunset. Reason : Sun rays have to pass through larger distance in atmosphere.
Check the correct statements on scattering of light S1 : Rayleigh scattering is responsible for the bluish appearance of sky S2 : Rayleigh scattering is proportional to 1//lambda^(4) when the size of the scatterer is much less than lambda S3 : Clouds having droplets of water (large scattering objects) scatter all wavelengths are almost equal and so are generally white S4 : The sun looks reddish at sunset and sunrise due to Rayleigh scattering
Assertion : The sun lookes bigger in size at sunrise and sunset than during day. Reason : The phenomenon of diffraction bends light rays.
Explain the following observations. a. Sun looks red at the time of sunset. b. Rate of physical adsorption decreases with rise in temperature. c. Physical adsorption is monolayered.
Why does the Sun appear reddish at the time of sunset ?