1、附件 1：2014 年第一届河北省大学生物理竞赛（实验部分）竞赛题目复赛题目（五选四）：1. Invent yourself It is known that some electrical circuits exhibit chaotic behaviour. Build a simple circuit with such a property, and investigate its behaviour.自己创造据了解，一些电路表现出混沌行为。构建一个具有这样属性的简单电路，并研究其行为。2. Twisted rope Hold a rope and twist one end of i
2、t. At some point the rope will form a helix or a loop. Investigate and explain the phenomenon.扭曲的绳握住绳子扭它的一端。在绳索上的某一点将形成螺旋线或圆环。调查解释这样的现象。3. Loaded hoop Fasten a small weight to the inside of a hoop and set the hoop in motion by giving it an initial push. Investigate the hoops motion.载物的环在一个环的里面固定一个小重
3、物，给环一个初始推力使其运动。研究环的运动。4. Coefficient of diffusion Using a microscope, observe the Brownian motion of a particle of the order of micrometre in size. Investigate how the coefficient of diffusion depends on the size and shape of the particle.扩散系数利用显微镜按微米大小的顺序观察微粒的布朗运动。研究扩散系数是如何取决于微粒的大小和形状的。5. Oil stars
4、 If a thick layer of a viscous fluid (e.g. silicone oil) is vibrated vertically in a circular reservoir, symmetrical standing waves can be observed. How many lines of symmetry are there in such wave patterns? Investigate and explain the shape and behaviour of the patterns.油星星如果一层厚厚的粘性流体（如硅油）在一个圆形的水槽
5、里上下振动，可以观察到对称驻波。在这样的波图案中有多少条对称的线？研究并解释图案的形状和行为。决赛题目：1. Pot-in-pot refrigerator The pot-in-pot refrigerator is a device that keeps food cool using the principle of evaporative cooling. It consists of a pot placed inside a bigger pot with the space between them filled with a wet porous material, e.g.
6、sand. How might one achieve the best cooling effect?“罐中罐冰箱”这一个依据蒸发冷却的原理让食物保鲜的装置。它包括一个大容器、里面的小容器。它们之间的空间内用湿的多孔材料填充，例如沙子。问怎么能达到最佳的散热效果？2. Rubber motor A twisted rubber band stores energy and can be used to power a model aircraft for example. Investigate the properties of such an energy source and how its power output changes with time.橡胶电机扭曲的橡皮筋存储着能量，例如可以用于驱动飞机模型。调查这样的能量来源的属性及其功率输出随时间的变化。3. Magnetic brakes When a strong magnet falls down a non-ferromagnetic metal tube, it will experience a retarding force. Investigate the phenomenon.磁力刹车当一个强磁铁从非铁磁性金属管内降下来时，它会经历一个阻滞力，研究这个现象。
