Question

How does specific heat of a heated object affect temperature change when placed in water?

For example, how would a heated penny (0.380 J/gC) change the temperature of water compared to a heated copper coupling (0.385 J/gC)?

Answer 1

See Below

Explanation:

Specific heats really dictate how much energy will be needed to raise the temperature of some substance (or lower the temp). They are specific for each individual substance.
The specific heat for water is over 10x higher than for the copper penny.

So you've got this really hot penny and you drop it into a bit of water. After all is said and done, they'll both be the same temperature. The penny lands in the water and immediately starts to offload its Energy to the water.
The penny is say 1g at 100C. Even if the temperature change was down to 20C, it is only dropping off `0.38xx1xx80`, or about 30.40J.

The water on the other hand, lets say 1g with a heat capacity of 4.184J/gC - its change in temperature when this hot penny drops in will be 7.3 degrees celcius.

So the penny changed in temperature by something like 80degrees, while the penny jumped up by 7.3 degrees. That is siimply because water takes so much more energy to change its temperature (per gram).

Now if this had been a penny pressed to some copper, well they have almost the same specific heat. So if you had the penny at 100C and the copper at 20C, you'd expect they'd both have approximately the average of their two temperatures when they are finished. About 60C. so the copper would heat by 40C, while the penny would cool by 40C.