我们已经论述过,热能只有在从高温物体向低温物体传递时,才能被感觉出来。因此,温度计的作用有赖于某些热能从被测量温度的物体或物质传递给温度计,以便使温度计内的水银膨胀,从而显示出一定的温度来。但是,这种传递是怎样发生的呢? 如果我们触摸某一热的物体时,我们就会被灼痛,这种灼痛的感觉是由物体的热能通过传导传递给手指而引起的,传导是热量通过物质传递的过程。如果我们在金属棒的一端加热而用手握住棒的另一端,则用不了多久,我们就会感到金属棒在逐渐变热。这是热传导的一个例子,在这一情况下,热是通过棒的金属传导的。并不是所有的物质的传导都是如此良好的。因此,可用木棍或塑料杆来做一次 We have already argued that the heat can only be felt when passing from high temperature objects to low temperature objects. Therefore, the function of the thermometer depends on the transfer of certain thermal energy from the object or substance at the temperature being measured to the thermometer in order to cause the mercury in the thermometer to expand, thereby exhibiting a certain temperature. But how does this transfer happen? If we touch a hot object, we are burned, and the sensation of burning is caused by the thermal energy of the object being transferred to the finger by conduction, which is The process of heat transfer through matter. If we hold the other end of the stick by heating it with one end of the stick, it will not take long before we feel that the stick is heating up. This is an example of heat conduction, in which case the heat is conducted through the metal of the rod. Not all material conduction is so good. Therefore, a stick or plastic rod can be used to do it once