Question

Which of the following containing same amount of boiling water is likely to cool first.
a) Beaker whose surface is covered with aluminium foil.
b) A beaker whose surface is painted black.

Answer 1

Heya......!!!

b ). A beaker whose surface is painted black will cool down first .

Because »» According to Kirchoff's laws of radiation Black body is Good emitter of heat ,,,Hence the black container will cool down faster. 

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