Cooling of an Object: Which Hypothesis is Correct?

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In summary, the question is about the behavior of a hot object placed on a slab at room temperature. The two hypotheses are: 1) the object will cool down due to conduction with the slab, convection with the surrounding air, and the emission of electromagnetic radiation, and 2) if the slab's emissivity is higher than the object's, the object may actually heat up. The use of the Stefan-Boltzmann law and the 2nd law of thermodynamics may be relevant in finding the correct answer.
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Homework Statement


An hot object is positioned on a slab at room temperature (20° C), which of that 2 ipothesis is correct?

1)The object will get cold because of the conduction with the slab, the convection af the air around the object and the electromagnetic radiations it send out.
2)If the slab emissivity is bigger than the object emissivity, the object could heat up.
Thanks!


Homework Equations



Stefen-Boltzmann law

The Attempt at a Solution


I don't know if the second ipothesis is correct and in the first the sending out of electromagnetic radiations can be a trick :(
 
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Looks like it's got something to do with the 2nd law of thermodynamics.
 

FAQ: Cooling of an Object: Which Hypothesis is Correct?

Why does an object cool down?

Objects cool down because they lose energy in the form of heat. This heat energy is transferred from the object to its surroundings, causing the object's temperature to decrease.

How does the surrounding temperature affect an object's cooling rate?

The surrounding temperature can greatly affect an object's cooling rate. If the surrounding temperature is lower than the object's temperature, the object will cool down faster. If the surrounding temperature is higher, the object will cool down slower.

Is the rate of cooling the same for all objects?

No, the rate of cooling can vary depending on the object's size, shape, material, and temperature. Objects with a larger surface area or made of materials that conduct heat well will typically cool down faster than objects with a smaller surface area or made of materials that are less conductive.

What is the difference between conduction and convection in the cooling process?

Conduction is the transfer of heat between objects that are in direct contact with each other, while convection is the transfer of heat through the movement of fluids (such as air or water). In the cooling process, both conduction and convection can play a role depending on the surrounding temperature and the object's properties.

How can we measure an object's cooling rate?

An object's cooling rate can be measured by using a thermometer to track its temperature over time. This can be done by recording the temperature at regular intervals and plotting it on a graph. The slope of the graph will indicate the rate of cooling, with a steeper slope indicating a faster cooling rate.

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