Question

A red rose when seen green light appears black please tell me why

Answer 1

Let's say you flash white light on the flower. The reason it appears red is because it reflects red colour and absorbs the rest. Hence whengreen light is shone on it, it absorbs all of the green light and not reflecting anything. Hence, itappears black.

Answer 2

A red flower appears red because when a normal visible light falls on the flower it absorbs all other colours except the red.(a normal visible light has all the seven colours). As the red colour is reflected, we see it red. Now, if you use green light to see the flower, then the flower will absorb it and nothing will be reflected. That's why you will see it black, lack of light

                                   

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