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A piece of charcoal and a piece of shining steel of the same surface area are left for a long time in an open lawn in bright sunlight. Which statement is correct?

1. The steel absorbs more heat than the charcoal.
2. The temperature of the steel becomes higher than that of the charcoal.
3. If both are picked up with bare hands, the steel feels hotter than the charcoal.
4. If both are then moved into a cold chamber, the charcoal loses heat faster than the steel.

Correct answer: If both are then moved into a cold chamber, the charcoal loses heat faster than the steel.

Solution

Charcoal, being black, is both a better absorber and better emitter than shiny steel; so in the cold chamber it radiates (loses) heat faster.

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