Decreasing Temparature

[binosh1]

Can anyone tell me why temperature falls faster when it is at the top end of 100 degrees and why it slows down when it is near room temp? stupid question but im bored and wana know!

[swansont]

Can anyone tell me why temperature falls faster when it is at the top end of 100 degrees and why it slows down when it is near room temp? stupid question but im bored and wana know!

 

Because the rate of heat flow is proportional to the temperature difference for conduction, and to the difference of the fourth power of temperature for radiation.

[Sisyphus]

I assume you're talking about an object in the room that is hot but then cools off. In that case, I believe it's because the heat is transferred from object to room by the collision of the molecules of object and air. If the object is hotter, its molecules are moving more quickly on average. The bigger the difference in temperature, the bigger the difference in speed, which means the bigger the difference in energy. So say the average air molecule has 1 unit of energy, and the average object molecule has 10 units. When they collide, the total energy is conserved, but some is exchanged. And so, on average, the air is going to gain energy and the object is going to lose some, causing the object to cool and the air to warm. Later, let's say the average air energy is 5 and the average object energy is 6. You can see that, on average, the object is going to lose less energy per collision, and so the temperature change slows down.

[binosh1]

thanks both for responding thats helped clear things up!!