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NTA Abhyas JEE Main2020PhysicsThermal Properties of MatterPractice

A polished metal plate with a rough black spot on it is heated to about 1400 K and quickly taken to a dark room. The spot will appear

Options

  1. ADarker than plate
  2. BBrighter than plate
  3. CEqually bright
  4. DEqually dark

Correct answer

B. Brighter than plate

Step-by-step solution

On heating, black spot absorbs maximum radiation. Therefore, when plate is taken to a dark room the spot will emit more radiations than the rest of the plate. Hence, it will appear brighter than the plate.

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