灰热的夏夭，男女老少均视扇子为心爱之物，一扇在手，可以驱蚊防暑．难道扇扇子可以降低周围空气的温度？否．如果我们用扇子扇温度计，或把温度计置于电扇正在工作的房间里，结果会发现温度计的示数不会降低．为什么扇扇子感到凉快呢？我们可以做这样的实验，在温度计的玻璃 The gray and hot summer cicada, both male and female, young and old, regard the fan as their favorite thing, and a hand in hand can repel mosquitoes and prevent heatstroke. Can fans reduce the temperature of the surrounding air? no. If we use a fan to fan the thermometer or put the thermometer in the room where the fan is working, the result will be that the number of thermometers will not decrease. Why does the fan feel cool? We can do this kind of experiment in the glass of the thermometer