A trekker in a dark forest at night notices three glowing things: a patch of bioluminescent mushroom on a…

A trekker in a dark forest at night notices three glowing things: a patch of bioluminescent mushroom on a tree trunk, the planet Venus shining overhead, and a cat's eyes glowing when torchlight hits them. Which of these is a natural luminous source of light?
  1. Only the bioluminescent mushroom
  2. The bioluminescent mushroom and planet Venus
  3. Planet Venus and the cat's eyes
  4. All three of them

Solution

The bioluminescent mushroom produces its own light through internal chemical reactions, making it a luminous source. Venus and the cat's eyes only reflect light originating from other sources.

Asked in: Homi Bhabha Practice

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