Two identical empty metal containers P and Q are placed over identical Bunsen burners and the burners lit. P is dull black while Q is shiny bright. After each container attains a temperature of #100^0C#the burners are turned off. Two identical test tubes containing water are suspended in each container without touching the sides as shown in figure 3.

Explain why container Q may become hot faster than P

Answer:

- P losses more heat supplied by the burner than Q because dull surfaces are good emitters of heat. Q being a shiny surface, is a poorer radiator of heat thus retains more heat absorbed.

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