Why does aluminum foil absorb heat?

Answer 1

== Aluminum foil absorbs heat because the foil, like anything else, will absorb energy from a heat source according to thermodynamic principles. What that translates into is this: heat goes from where it is to where it isn't, or heat goes from where it's hot to where it's not. There are three ways for that to happen. One is convection, one is radiation and the third is conduction. If foil is exposed to flame, the hot combustion gases directly heat the foil when they come in contact with it. If the foil is sitting on the top of the range when the oven is on, the oven heats the air around it and convection currents are set. These convection currents take heat away from the oven and transfer it to things which the hot air passes over. Anyone who has had a hair dryer pointed at them knows what this is like. The skin reacts to the hot air. We feel it. Convection. In a situation where the foil is exposed to radiant energy, infrared radiation, it will react to the incoming radiation by absorbing some of it. Radiation happens because something that is hot is generating heat radiation (electromagnetic waves that are below the optical or visible spectrum). And the foil catches some of them without reflecting them. It absorbs the energy and gets warmer. The best "life experience" example of this kind of radiation may be something familiar. If we suffer a sunburn on our face, the skin is sensitized to heat by the trauma. If we wander into the kitchen where things are cooking on the stove top and look at the stove from fairly close, we might notice a bit of pain where we were burned. That's direct heat (infrared) radiation striking the skin of the face. Another example might be looking into a fireplace through a glass screen. If the fire is hot and we are close enough, we can feel the heat on our face because a bunch of infrared radiation makes a direct route from the fire through the glass and onto our skin. Conduction is the transfer of heat in matter that is touching; for example, from one end of a metal bar to the other end, or from a metal bar that is touching another metal bar.

Answer 2

Aluminum foil absorbs heat because it has high thermal conductivity, meaning it can transfer heat quickly. When placed in an oven or wrapped around food, aluminum foil absorbs and transfers heat effectively, helping to cook food faster and more evenly.