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Temperature and Heat
Three Ways Heat Moves Between Objects
Description
Heat transfer happens when there is a temperature difference. It can move fast, like through a cooking pan, or slowly, like through the walls of a picnic ice box. Heat transfer appears in many everyday situations, so it is hard to find a place where it does not occur.
There are only three ways he...
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Transcript
热传递的例子不胜枚举,例如因握住热锅而烫伤皮肤、煮沸牛奶,或在微波炉中加热食物。
当存在温度梯度时,热传递可以通过三种方式进行:传导、对流和辐射。
热传导是指热量在一个物体内部或两个物理接触的物体之间从高温区域向低温区域传递的过程。
例如,如果将一个平底锅放在火焰上方,热量会传递到锅上,最终使其变热。
此外,如果将一把钢勺的一端置于火焰上方,由于热传递,另一端会变热。
在热传导过程中,高温区域的分子具有较高的动能。它们与低温区域的分子发生碰撞,并将能量传递给后者。
热传导的传热速率由一个涉及温度梯度、表面积以及热量流经材料厚度的方程给出。
'k' 是材料的热导率,导体的热...
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