Name: Alex Botvinnik
Status: N/a
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993
Question:
How come when I put a pizza in the oven, the aluminum foil does
not get hot?
Replies:
It (aluminum foil) DOES get hot. In fact it gets hot much more
quickly than the nearby pizza. It also cools off much more quickly, which is
why we tend to think of it as not getting hot. Here is the deal: At any
given temperature, aluminum holds much less energy than an equivalent mass of
pizza (or an equivalent mass of human flesh--and now we are getting to the
point). When you touch the aluminum foil, your hand and the foil share the
thermal energy in the foil. Your hand says "big deal! It takes MUCH more
energy to raise my temperature because I am made mainly of water" (and water
is phenomenal in its ability to hold energy without increasing temperature
much). However, it is also true that the aluminum foil is much less massive
than your hand, and so part of the answer is that there is just not much foil
there. And its also true that the air cools thefoil more quickly than the
pizza since the foil has more surface area in addition to holding less energy
per degree of temperature.
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