IYPT全球青年物理學家錦標賽 2018年真題

International Young Physicists’ Tournament

IYPT全球青年物理學家錦標賽

2018年真題（附中文翻譯）

 

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真題中文翻譯

僅供參考

Invent Yourself

制作一個保護生雞蛋的被動裝置，使得生雞蛋從2.5m的高度落到硬表面時能夠安全著陸。該裝置必須與雞蛋一同落下。你能做到的該裝置的最小尺寸是多少？

Colour of Powders

如果將有色材料研磨成粉末，在某些情況下，所得到的粉末可能具有與原始材料不同的顏色。調查研磨程度如何影響粉末的表觀顏色。

Dancing Coin

把一個硬幣放在一個極度冷卻的瓶子的瓶頸口上，一段時間后你會聽到聲音并觀察到這個硬幣的運動。解釋這一現象，并調查相關參數如何影響這個舞蹈。

Heron’s Fountain

構造一個海倫噴泉并解釋它怎樣工作。研究相關參數是如何影響水柱高度的。

Drinking Straw

當吸管放置在碳酸飲料中時，它可能會浮起來，甚至有時候會翻倒在杯沿上。請研究并結束吸管的運動，解釋吸管會翻倒的條件。

Ring Oiler

先讓涂油的水平圓柱軸以恒定的速度饒其軸線旋轉，再用紙板制作一個圓環，內徑為軸直徑的兩倍，并將其放在圓柱軸上。由于傾斜，圓環可以沿著軸的任一方向行進。請研究這個現象。

Conical Piles

非粘性顆粒材料可以被澆筑成一個圓錐型的樁。研究影響椎體形成的參數及其與地面的角度。

Cusps in a Cylinder

一個水平圓柱內部分填充粘性流體，當圓柱體繞其軸線旋轉時，可以觀察到異常的流體行為，如圓柱體壁上的尖端形狀。研究這個現象。

Candle in Water

當給在水中的蠟燭加些重量后，他就幾乎無法在水中漂浮。但是當蠟燭燃燒時，它可能繼續漂浮在水面。請研究并解釋這個現象。

Tesla Valve

特斯拉閥是一個固定幾何形狀的、被動式單向閥（瓣膜管道）。選定一個方向后，一個特斯拉閥可以在相反方向上提供了一個大得多的流動阻力（即提供單向流體通道）。請創建一個這樣的特斯拉閥并研究其相關參數。

Azimuthal-Radial Pendulum

將水平彈性桿的一端固定在剛性支架上。用一根繃緊的繩子支撐彈性桿的另一端以避免垂直偏轉，并將一個垂擺從另一根弦上懸掛下來（如圖所示）。在產生的鐘擺運動中，徑向震蕩（平行于桿）可以自發的轉變為方位震蕩（垂直于桿），反之亦然。研究這個現象。

Curie Point Engine

制作一個可以繞軸自由旋轉的鎳盤，在圓盤的邊緣放一塊磁鐵并加熱這一面。圓盤開始旋轉。請研究影響旋轉的參數并對圓盤的穩定運動做優化設計。

Weighing Time

眾所周知，沙漏的質量（以某種方式稱量）會隨沙子的流動而發生變化，請研究這一現象。

Radiant Lantern

在晚上給一個點燃的提燈拍照，會有大量從提燈中心發出的光線顯示在照片上，請研究并解釋這一現象。

Blowing Bubbles

當你吹一個有肥皂泡膜的圓環時，可能會吹出一個肥皂泡泡。而這個肥皂泡的液體表面會破掉也可能會繼續存在。請嘗試研究相關參數如何決定一個液面可以生成的泡泡數量以及生成的泡泡特征。

Acoustic Levitation

較小的物體可以在聲學駐波中懸浮，試著研究這一現象。請問你可以多大程度的操縱這個物體？

Water Bottle

當下有個十分熱門的水瓶投擲游戲：把一個半滿的塑料水瓶扔到半空中，它會翻幾個筋斗后平穩垂直的掉落在水平面上。請研究這個現象并解釋什么樣的參數可以使游戲成功。