Your cousin takes some hot cookies out of the oven and puts them on a rack to cool down. He notices that while the cookies are cooling down the temperature of the kitchen does not change much at all. He wonders how it is possible for the temperature of the cookies to change so much while the temperature of the kitchen does not change. Explain how this is possible. (Use diagrams, graphs, words and videos).
There are several processes and parts that act when placing the cookies out of the oven and onto the rack such as: conduction-convection-radiation-insulation.
Conduction is the physical transport of heat through stationary substance.
Radiation is heat transfer that happens when microwaves, infrared radiation, visible light, or other electromagnetic radiation is emitted or absorbed.
Convection is heat exchange through the macroscopic movement of fluids.
1. Conduction: In this instance, heat energy is being radiated as infrared radiation by the hot cookies. The walls, ceiling, and other surfaces in the kitchen may soak up this radiation as it passes through the air. The quantity of heat transferred and convected away from the cookies, however, far outweighs the thermal radiation that they emit. Initially, the temperature of the cookies is higher than that of the kitchen's ambient air. As a result, the cookies' heat energy is transmitted to the molecules of cooler air that are in close range to them.
2. Convection: As the air molecules close to the cookies warm up, they become less dense and rise, displacing them with colder air from other parts of the room. As a result, a convection current forms, which guarantees the warm air surrounding the cookies continually gets replaced with cooler air.
3. Radiation: Initially, the temperature of the cookies is higher than that of the kitchen's ambient air. As a result, the cookies' heat energy is transmitted to the molecules of cooler air that are in close range to them.
- It's crucial to note that even while the temperature of the cookies is dropping, the kitchen's overall temperature does vary slightly. The modification, yet, is rather slight and might not be obvious at all.
This is really well organized and explained!! Thank you for your help!!
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