摘要
利用热力学知识解释了橡皮筋受热收缩的原因.使用电子秤测量橡皮筋所受的熵力,并用温度拟合的结果得出橡皮筋定长时熵力与温度的关系,研究了橡皮筋伸长时内能的变化和熵的变化对张力的贡献.实验结果表明:常温下橡皮筋的弹力主要由构像熵引起.利用橡皮筋热缩性质制作了橡皮筋热机,当光照角度为-30°时热机平均转动速率最大,热机转动最为顺畅.
The reason of thermal shrinkage of rubber band was described by thermodynamic theory.Entropic force was measured by electric balance,its temperature dependence was determined for fixed length.When a rubber band was stretched,the contribution of the changes of internal energy and entropy to tension was studied.The experimental results indicated that the tension of rubber band was mainly caused by conformation entropy in room temperature.A heat engine was made based on the thermal shrinkage of rubber band.When the incident angle of light was-30°,the average rotating speed of the heat engine reached maxima,and the heat engine rotated swimmingly.
出处
《物理实验》
2014年第6期7-11,共5页
Physics Experimentation
关键词
橡皮筋
热缩性质
熵力
内能
热机
rubber band
thermal shrinkage
entropic force
internal energy
heat engine
