CBSE notes-Light

CBSE notes-Light

A beam of red light is allowed to fall in turn on
(a) a black cloth
(b) red cloth
(c) white cloth
(d) blue cloth. Describe and explain the appearance in each case.

(a) When red light falls on a black cloth it still appears black, because it does not reflect the red colour instead, it absorbs the light falling on it.
(b) When red light falls on a red cloth it still appears red, because it reflects only that colour.
(c) When red light falls on a white cloth it changes to a red coloured cloth, because the white cloth reflects the red colour of the light.
(d) When red light falls on a blue cloth it changes to black coloured cloth, because there is no blue colour in the red light which can be reflected

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