Question

Four metal cans are identical except for the colour and texture of the outer surfaces.100cm³ of water at 70°C is poured into each can. Which can cool the most rapidly?

Answer 1

Explanation:

Black surfaces are the best emitters and abosrbers of heat radiation and shiny surfaces are the poor abosrbers of heat radiation.

Therefore, The can that is black and has rough surface will radiate heat faster and hence, the water in can P will cool down most rapidly.