MCQ
When red glass is heated in dark room it will seem
  • Green
  • B
    Purple
  • C
    Black
  • D
    Yellow

Answer

Correct option: A.
Green
a
(a) Red and green colours are complementary to each other.

When red glass is heated it absorbs green light strongly, hence according to Kirchoff’s law, the emissive power of red glass should be maximum for green light.

That’s why when this heated red glass is taken in dark room it strongly emits green light and looks greenish.

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