Q.26 Give reasons :-
a) Colour of sky appears blue.
b) We see rainbow only after rainfall.
Answers
Question :
Colour of sky appears blue.
Answer :
Gases and particles in Earth's atmosphere scatter sunlight in all directions. Blue light is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.
Question :
We see rainbow only after rainfall.
Answer :
After a shower of rain, rain drops are suspended in air and when a ray of light enters this drop, the drop acts as a prism and splits into its component colors as dispersion takes place. Lights of different colours emerge from the rain drops such as red at the top and violet at the bottom. Thus, a rainbow is formed.
Why is the sky blue in Class 12?
The scattering of light by a molecule is inversely proportional to the fourth power of wavelength of light . Thus the sky appears blue because the scattered light has a large mixture of shorter wavelength light (violet and blue) than of longer wavelength light (Yellow and red).Jun
Why is sky blue in Colour Class 9 Chemistry?
The sunlight that reaches the earth's atmosphere is scattered in all directions by the gases and dust particles present in the atmosphere. The blue colour is scattered more and hence the sky appears blue. ... So blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere.
a) This is because the sun emits a higher concentration of blue light waves in comparison violet. Furthermore, as our eyes are more sensitive to blue rather than violet this means to us the sky appears blue.
b) After a shower of rain, rain drops are suspended in air and when a ray of light enters this drop, the drop acts as a prism and splits into its component colors as dispersion takes place. Lights of different colours emerge from the rain drops such as red at the top and violet at the bottom. Thus, a rainbow is formed.