2014年IYPT竞赛题目
发布：王超 来源：物理教研组 日期：2018-12-18 人气：
1．“Invent yourself” 自己创造
It is known that some electrical circuits exhibit chaotic behaviour. Build a simple circuit with such a property, and investigate its behaviour.
据了解，一些电路表现出混沌行为。构建一个具有这种属性的简单电路，并研究其行为。
2．“Hologram” 全息照片
It is argued that a hologram can be hand made by scratching a piece of plastic.
Produce such a ‘hologram’ with the letters ‘IYPT’ and investigate how it works.
有人认为，在一块透明塑料上划出图案可以手工制作出一张全息照片。制作一张字母“IYPT ”的全息图并研究它是如何工作的。
3．“Twisted rope” 扭曲的绳
Hold a rope and twist one end of it. At some point the rope will form a helix or a loop. Investigate and explain the phenomenon.
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。
4．“Ball sound” 球的声音
When two hard steel balls, or similar, are brought gently into contact with each other,an unusual ‘chirping’ sound may be produced. Investigate and explain the nature of the sound.
当两个硬钢球或类似的东西被轻轻带到接触到对方，一个不寻常的“鸣叫声”。调查解释的声音的性质。
5．“Loaded hoop” 载物的环
Fasten a small weight to the inside of a hoop and set the hoop in motion by giving it an initial push. Investigate the hoop’s motion.
在一个环的里面固定一个小重物，给环一个初始推力使其运动。研究环的运动。
6．“Bubble crystal” 泡泡晶体
A large number of very small, similar air bubbles float on the surface of a soapy liquid.The bubbles will arrange themselves into a regular pattern similar to a crystalline lattice. Propose a method to obtain bubbles of a consistent size, and investigate the formation of such a bubble crystal.
大量非常小的相似的气泡浮在肥皂水的表面上。气泡会自动按照一个规律的类似晶格的模式排列。提出一种获得大小一致的的气泡的方法，并探究这种泡泡晶体的形成。
7．“Pot-in-pot refrigerator” “罐中罐”冰箱
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. sand. How might one achieve the best cooling effect?
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？
8．“Freezing droplets” 冻结水滴
Place a water droplet on a plate cooled down to around -20 °C. As it freezes, the shape of the droplet may become cone-like with a sharp top. Investigate this effect.
将水滴放置在冷却到－20°C左右的板上。结冰后液滴可能会成为有锋利的顶部的圆锥状。调查这种现象。
9．“Water bombs” 水弹
Some students are ineffective in water balloon fights as the balloons they throw rebound without bursting. Investigate the motion, deformation, and rebound of a balloon filled with fluid. Under what circumstances does the balloon burst?
有些学生不会用灌水的气球打仗，他们的水弹反弹后仍不爆裂。调查这里的运动，变形和充满液体的气球的反弹。在什么情况下水弹会爆裂？
10．“Coefficient of diffusion” 扩散系数
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.
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。
11．“Candle Power Plant” 蜡烛发电厂
Design a device that converts the heat of a candle flame into electrical energy.
Investigate how different aspects of the device affect its efficiency.
设计一将蜡烛的火焰的热量转化成电能的装置。调查装置的不同方面如何影响其效率。
12．“Cold balloon” 冷气球
As air escapes from an inflated rubber balloon, its surface becomes cooler to the touch. Investigate the parameters that affect this cooling. What is the temperature of various parts of the balloon as a function of relevant parameters?
由于空气逃离橡胶气球，其表面触感变得冷。研究影响降温的参量。作为一个函数的相关参数，气球的不同部分温度是什么？
13．“Rotating saddle” 旋转的鞍
A ball is placed in the middle of a rotating saddle. Investigate its dynamics and explain the conditions under which the ball does not fall off the saddle.
一个球被放在旋转的鞍上。从动力学的角度研究它，解释球不会从鞍上落下来的情形。
14．“Rubber motor” 橡胶电机
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.
扭曲的橡皮筋存储着能量，例如可用于驱动飞机模型。调查这样的能量来源的属性及其功率输出随时间的变化。
15．“Oil stars” 油星星
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.
如果一层厚厚的粘性流体（如硅油）在一个圆形的水槽里上下振动，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。
16．“Magnetic brakes” 磁力刹车
When a strong magnet falls down a non-ferromagnetic metal tube, it will experience a retarding force. Investigate the phenomenon.
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。
17．“Chocolate hysteresis” 巧克力液固相变迟滞现象
Chocolate appears to be a solid material at room temperature but melts when heated to around body temperature. When cooled down again, it often stays melted even at room temperature. Investigate the temperature range over which chocolate can exist in both melted and ‘solid’ states and its dependence on relevant parameters.
巧克力于室温一般是固态，温度升至体温时则变液态，但一旦温度再次降低至室温则会维持液态不变。请就此现象作一个调查，得出使巧克力既能以固态存在又能以液态存在的温度范围以及这个范围所依赖的相关参数。
