Give reasons for the following : (a) Danger signals installed at airports and at the top of tall buildings…
Give reasons for the following :
(a) Danger signals installed at airports and at the top of tall buildings are of red colour.
(b) The sky appears dark to the passengers flying at very high altitudes.
(c) The path of a beam of light passing through a colloidal solution is visible.
Solution
(a) Red Coloured light is least scattered by fog or smoke and can be easily seen from a distance. / Red colour has high wavelength thus scattering is less.
(b) There is no scattering of light due to lack of atmosphere.
(c) Particles of colloid are big enough to scatter the beam of light.