IYPT全球青年物理学家锦标赛 2018年真题

International Young Physicists’ Tournament

IYPT全球青年物理学家锦标赛

2018年真题（附中文翻译）

 

The originator of a new concept finds, as a rule, that it is much more difficult to find

out why other people do not understand him, than it was to discover the new truth.
Hermann von Helmholtz

1. Invent Yourself Construct a simple seismograph that amplifies a local disturbance by mechanical, optical or electrical methods. Determine the typical response curve of your device and investigate the parameters of the damping constant. What is the maximum amplification that you can achieve?
2. Colour of Powders If a coloured material is ground to a powder, in some cases the resulting powder may have a different colour to that of the original material. Investigate how the degree of grinding affects the apparent colour of the powder.
3. Dancing Coin Take a strongly cooled bottle and put a coin on its neck.Over time you will hear a noise and see movements of thecoin. Explain this phenomenon and investigate how the relevant parameters affect the dance.
4. Heron's Fountain Construct a Heron’s fountain and explain how it works.Investigate how the relevant parameters affect the height of the water jet.
5. Drinking Straw When a drinking straw is placed in a glass of carbonated drink, it can rise up, sometimes toppling over the edge of the glass. Investigate and explain the motion of the straw and determine the conditions under which the straw will topple.
6. Ring Oiler An oiled horizontal cylindrical shaft rotates around its axis at constant speed. Make a ring from a cardboard disc with the inner diameter roughly twice the diameter of the shaft and put the ring on the shaft. Depending on the tilt of the ring, it can travel along the shaft in either direction.Investigate the phenomenon.
7. Conical Piles Non-adhesive granular materials can be poured such that they form a cone-like pile. Investigate the parameters that affect the formation of the cone and the angle it makes with the ground.
8. Cusps in a Cylinder A horizontal cylinder is partially filled with a viscous fluid.When the cylinder is rotated around its axis, unusual fluid behaviour can be observed, such as cusp-like shapes on the walls of the cylinder. Investigate the phenomenon.
9. Candle in Water Add some weight to a candle such that it barely floats in water. As the candle burns, it may continue to float. Investigate and explain this phenomenon. The originator of a new concept finds, as a rule, that it is much more difficult to find out why other people do not understand him, than it was to discover the new truth.
10. Tesla Valve A Tesla valve is a fixed-geometry, passive, one-direction valve. A Tesla valve offers a resistance to flow that is much greater in one direction compared to the other. Create such a Tesla valve and investigate its relevant parameters.
11. Azimuthal-Radial Pendulum Fix one end of a horizontal elastic rod to a rigid stand. Support the other end of the rod with a taut string to avoid vertical deflection and suspend a bob from it on another string (see figure). In the resulting pendulum the radial oscillations (parallel to the rod) can spontaneously convert into azimuthal oscillations (perpendicular to the rod)and vice versa. Investigate the phenomenon.
12. Curie Point Engine Make a nickel disc that can rotate freely around its axis.Place a magnet near the edge of the disc and heat this side of it. The disc starts to rotate. Investigate the parameters affecting the rotation and optimize the design for a steady motion.
13. Weighing Time It is commonly known that an hourglass changes its weight(as measured by a scale) while flowing. Investigate this phenomenon.
14. Radiant Lantern When taking a picture of a glowing lantern at night, a number of rays emanating from the centre of the lantern may appear in the pictures. Explain and investigate this phenomenon.
15. Blowing Bubbles When blowing on a soap film in a ring, a bubble may be formed. The liquid film may pop or continue to exist.Investigate how the number of bubbles produced from a single soap film and the characteristics of the bubbles depend on the relevant parameters.
16. Acoustic Levitation Small objects can levitate in acoustic standing waves.Investigate the phenomenon. To what extent can you manipulate the objects?
17. Water Bottle The current craze of water bottle flipping involves launching a partially filled plastic bottle into the air so that it performs a somersault before landing on a horizontal surface in a stable, upright position. Investigate the phenomenon and determine the parameters that will result in a successful flip.

2018年IYPT真题中文翻译

仅供参考

Invent Yourself

制作一个保护生鸡蛋的被动装置，使得生鸡蛋从2.5m的高度落到硬表面时能够安全着陆。该装置必须与鸡蛋一同落下。你能做到的该装置的最小尺寸是多少？

Colour of Powders

如果将有色材料研磨成粉末，在某些情况下，所得到的粉末可能具有与原始材料不同的颜色。调查研磨程度如何影响粉末的表观颜色。

Dancing Coin

把一个硬币放在一个极度冷却的瓶子的瓶颈口上，一段时间后你会听到声音并观察到这个硬币的运动。解释这一现象，并调查相关参数如何影响这个舞蹈。

Heron’s Fountain

构造一个海伦喷泉并解释它怎样工作。研究相关参数是如何影响水柱高度的。

Drinking Straw

当吸管放置在碳酸饮料中时，它可能会浮起来，甚至有时候会翻倒在杯沿上。请研究并结束吸管的运动，解释吸管会翻倒的条件。

Ring Oiler

先让涂油的水平圆柱轴以恒定的速度饶其轴线旋转，再用纸板制作一个圆环，内径为轴直径的两倍，并将其放在圆柱轴上。由于倾斜，圆环可以沿着轴的任一方向行进。请研究这个现象。

Conical Piles

非粘性颗粒材料可以被浇筑成一个圆锥型的桩。研究影响椎体形成的参数及其与地面的角度。

Cusps in a Cylinder

一个水平圆柱内部分填充粘性流体，当圆柱体绕其轴线旋转时，可以观察到异常的流体行为，如圆柱体壁上的尖端形状。研究这个现象。

Candle in Water

当给在水中的蜡烛加些重量后，他就几乎无法在水中漂浮。但是当蜡烛燃烧时，它可能继续漂浮在水面。请研究并解释这个现象。

Tesla Valve

特斯拉阀是一个固定几何形状的、被动式单向阀（瓣膜管道）。选定一个方向后，一个特斯拉阀可以在相反方向上提供了一个大得多的流动阻力（即提供单向流体通道）。请创建一个这样的特斯拉阀并研究其相关参数。

Azimuthal-Radial Pendulum

将水平弹性杆的一端固定在刚性支架上。用一根绷紧的绳子支撑弹性杆的另一端以避免垂直偏转，并将一个垂摆从另一根弦上悬挂下来（如图所示）。在产生的钟摆运动中，径向震荡（平行于杆）可以自发的转变为方位震荡（垂直于杆），反之亦然。研究这个现象。

Curie Point Engine

制作一个可以绕轴自由旋转的镍盘，在圆盘的边缘放一块磁铁并加热这一面。圆盘开始旋转。请研究影响旋转的参数并对圆盘的稳定运动做优化设计。

Weighing Time

众所周知，沙漏的质量（以某种方式称量）会随沙子的流动而发生变化，请研究这一现象。

Radiant Lantern

在晚上给一个点燃的提灯拍照，会有大量从提灯中心发出的光线显示在照片上，请研究并解释这一现象。

Blowing Bubbles

当你吹一个有肥皂泡膜的圆环时，可能会吹出一个肥皂泡泡。而这个肥皂泡的液体表面会破掉也可能会继续存在。请尝试研究相关参数如何决定一个液面可以生成的泡泡数量以及生成的泡泡特征。

Acoustic Levitation

较小的物体可以在声学驻波中悬浮，试着研究这一现象。请问你可以多大程度的操纵这个物体？

Water Bottle

当下有个十分热门的水瓶投掷游戏：把一个半满的塑料水瓶扔到半空中，它会翻几个筋斗后平稳垂直的掉落在水平面上。请研究这个现象并解释什么样的参数可以使游戏成功。