南洋中学首届校园CYPT物理学术竞赛赛题

1. Artificial Muscle

Attach a polymer fishing line to an electric drill and apply tension to the line. As it twists, the fibre will form tight coils in a spring-like arrangement. Apply heat to the coils to permanently fix that spring-like shape. When you apply heat again, the coil will contract. Investigate this ‘artificial muscle’.

2. Two Balloons

Two rubber balloons are partially inflated with air and connected together by a hose with a valve. It is found that depending on initial balloon volumes, the air can flow in different directions. Investigate this phenomenon.

3. Magnus Glider

Glue the bottoms of two light cups together to make a glider. Wind an elastic band around the centre and hold the free end that remains. While holding the glider, stretch the free end of the elastic band and then release the glider. Investigate its motion.

4. Hovercraft

A simple model hovercraft can be built using a CD and a balloon filled with air attached via a tube. Exiting air can lift the device making it float over a surface with low friction. Investigate how the relevant parameters influence the time of the 'low-friction' state.

5. Thick Lens

A bottle filled with a liquid can work as a lens. Arguably, such a bottle is dangerous if left on a table on a sunny day. Can one use such a ‘lens’ to scorch a surface?

参考翻译及参考实验图片(所有题目以英文原版为准,以下资料仅供参考)

1、人造肌肉/伪肌肉(Artificial muscle) 

 

将一个多聚物钓鱼线固定(attach)在电钻上并使其绷紧。当它扭转时,钓鱼线纤维会形成像弹簧一样排列的牢固的线圈。对线圈加热使它定型,成为弹簧一样的形状。当你再次加热时,线圈会收缩。研究这个"人造肌肉"

 

2、双气球(Two balloons) 

 

两个橡胶气球被不完全充满气并被一个带阀的塑料管(hose)连接。会发现空气由于初始气球体积不同而流向不同方向这样的现象。研究这个现象。

 3、马格努斯滑翔机(Magnus glider) 

 

将两个轻质杯子的底部粘在一起来制作一个滑翔机。将一根弹性带子(band)缠绕在滑翔机的中心并抓住余下的自由端。当握着滑翔机时,拉伸带子的自由端然后释放滑翔机。研究它的运动。

4.气垫船(Hovercraft) 

 

将一张CD光盘和一个充满气的气球通过一根管子连接。漏气可以升起装置使其以低摩擦漂浮在一个表面上。研究相关参量如何影响"低摩擦"状态持续的时间。

5、厚透镜(Thick lens) 

 

一个装满液体的瓶子可以用作透镜。有人认为(arguably)如果将这样的瓶子在晴天放在桌子上会造成危险。可以用这样的"透镜"来烤焦一个表面吗?