Which would heat up faster, a substance with a low specific heat capacity or something wth a high specific heat capacity? Explain reasoning.
Wed, 2012-03-07 13:40
Clearly specific heat capacity means amount of heat required to raise the temperature of 1 grams of substance by 1 degree celcius... this means that if you have susbtance A that has a high specific heat, and B with a low specific heat but mass of both susbtance are equal, you're going to have to put more heat into substance A in order to get the same temperature change as substance B.
Put another more general way: it is difficult to change the temperature of substances with a high specific heat because they resist change in temperature.
It should be clear to you now.............
Aluminum 0.91 kJ/kg.K
Copper 0.39 kJ/kg K
This means that if you had 1 kg of each, you would need 0.91kJ to raise the temp. of Al by 1K (or 1C) but would only need 0.39 kJ for the same change in copper. So the same amount of heat would give a greater rise in temperature with copper.
q=cmDeltaT is important where q= amount of heat, c= specific heat, m= mass of metal and DeltaT is the temperature change. Delta T = q/cm
So if you have 100 kJ of energy and 1 kg of copper and aluminium, the temperature change for aluminium would be = 100/0.91 x 1 = 110 C but for copper it would be 100/0.39 x 1 = 256C. So the smaller the specific heat value, the higher the temperature rise.
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