Question

HEAT TRANSFER (page 6)

Imagine that a 500 gram piece of hot iron at 100 degrees C is placed into a half liter (500 grams) of water at 20 degrees C in an insulated container.

A) If you were to measure the temperature of the iron and of the water at a later time, would you expect the temperatures to be the same or different? Would you expect each temperature to be above, below, or equal to 60 degrees C? Clearly explain your reasoning.

B) Explain how the concept above is related to some scientists' argument that the small but steady rise in ocean temperatures over the past 50 years is one of the clearest indicators of significant global warming

Answer 1

A) If you were to measure the temperature of the iron and of the water at a later time, would you expect the temperatures to be the same or different? Would you expect each temperature to be above, below, or equal to 60 degrees C? Clearly explain your reasoning.

The temperatures of the iron and water would be same. The metal, whcih was at a higher temperature, would transfer its heat to water and they both would reach an equilibrium temperature. I would expect it to be below 60 degrees. The average of the initial and final temps is (100+20)/2 = 60. Since there may not be a perfect equilibrium and some heat loss may occur in the prcess, I would expect the temp to be below 60.

B) Explain how the concept above is related to some scientists' argument that the small but steady rise in ocean temperatures over the past 50 years is one of the clearest indicators of significant global warming

The rise in ocean temperatures is also a result of similar heat trasnfer from various gases on earth and the earth itself. Earth and the other gases abosrb the heat directly from sun. Oceans, are intially at a lower temperature. But when equilibrium is establised, the heat trasfer from the earths surface and other gases (green house effect)takes place and the oceans wil have a rise in their temperatures.