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प्रश्न
Draw a labelled diagram to show (i) reddish appearance of the sun at the sunrise or the sunset and (ii) white appearance of the sun at noon when it is overhead.
उत्तर
i) The reddish appearance of the sun at sunrise or sunset is due to the scattering of light by the molecules of air and other fine particles in the atmosphere that have the size smaller than the wavelength of visible light from the sun near the horizon. Light travels larger distances at the horizon in the earth's atmosphere before reaching our eyes and most of the blue light and shorter wavelengths are scattered away by the particles. So, only red light, being of higher wavelength reaches us which gives the reddish appearance of the sun at sunrise or sunset.
ii) At noon, the sun appears white, not red, as only a little of the blue and violet colors are scattered because light from the Sun overhead would travel a relatively shorter distance.
संबंधित प्रश्न
Why does the sun appear reddish early in the morning? Will this phenomenon be observed by an observer on the moon? Justify your answer with a reason.
Which colour of the spectrum has
shortest wavelength?
How many colours are there in a full spectrum of white light? Write the various colours of spectrum in the order, starting with red.
What colour does the sky appear to an astronaut?
Out of blue light and red light, which one is scattered more easily?
Explain in brief the reason for the following :
Advanced sunrise
Explain in brief the reason for the following :
Delayed sunset
Blue litmus is added to two test tubes A and B containing dilute HCl and NaOH. Answer respectively. In which test tube a colour change will be observed? State the colour change and give its reason.
The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light ____________.
Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?
