听到物理这两个字时，你的第一个反应是什幺呢？感到头痛，还是毫无兴趣？作为一门学科，物理或许不是那幺讨喜，但在生活中我们处处可以见到物理学的印证，而且它们就跟变魔术一样神奇！IG上的physicsfun就致力以一些简单的实验来让我们看到物理知识，证明物理也能带来无限乐趣！
▼1. 要如何创造出自走的火车？只要在一颗电池的两端吸附上磁铁，再让它穿过铜线圈，电池就会自动跑起来了！原因是磁铁能引导电力，所以电池週边形成了磁场，进入线圈时这个磁力与铜线产生作用，便会推动它前进。
Faraday Train: two magnets, one battery, and a coil of bare copper wire are the simple essence of this self propelled craft. The magnets conduct electricity, thus when put in contact with the coil current will flow creating a solenoidal magnetic field in the vicinity of the battery, which in turn pushes on the magnets at each end of the battery moving the craft along. The spherical neodymium magnets used allows the craft to slide along the coil with minimal friction. ➡️ Follow the link in my profile to buy the parts to make your own and to find many of the items featured here on @physicsfun #faraday #faradaytrain #physics #physicstoy #coil #solenoid #electromagnet #electromagnetism #neodymium #magnet #ampere #ampereslaw #magneticfield #magneticrepulsion #magneticforce #science #maker #dyi #scienceisawesome #backemf physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 17 9:01上午 PST 张贴
▼2. 混合光的三原色红、绿、蓝之后，就可以得到黄色、洋红、青色，这在小球上的投影清晰地显示出来了！
RGB Color Addition: three LED light boxes demonstrate the additive nature of colored light. Mixing Red, Green, and Blue to create Yellow, Magenta, and Cyan. An object casts shadows showing the following mixings: R+G=Y, G+B=C, and R+B=M. Adding all three R+G+B produces White (a little pinkish here as the Red is a little bit bright for complete white balance). RGB color addition is the basis for all computer and TV displays- all the colors you are looking at right now on your screen are made from adding pixels of R G and B in different proportions and intensities! ➡️ This video features Light Blox available from Laser Classroom @laserclassroom. Follow the link in my profile for info on where to get these and many other items featured on @physicsfun. #physics #physicstoy #RGB #RGBcolor #optics #shadow #coloraddition #visualperception #colorperception #science #wavelength #frequency #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 21 10:36上午 PST 张贴
▼3. 只要把一小块钕的磁性立方体，放在磁性相异的热解石墨中，产生的磁力作用就会让小立方体不停跳舞。
Diamagnetic Trap Levitation: tiny neodymium cube magnet trapped between two diamagnetic discs of pyrolytic graphite. Diamagnetic substances only have magnetic fields of their own when placed in an external magnetic field from another source- here the cube shaped magnet supplies the field. Diamagnetic fields are pretty weak, so the top magnet is adjusted to help lift the tiny magnet against gravity where the slightest air currents can send it dancing. ➡️ Follow the link in my profile for info on where to get a device like this one and many of the items featured here on @physicsfun #diamagnetism #physics #physicstoy #neodymium #magneticfield #magnetism #levitation #maglev #science #pyrolyticgraphite #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 22 8:46上午 PST 张贴
▼4. 平行的玻璃镜面创造出了光的折射与反射，让蜡烛的火光有了无限延伸的错觉。
Infinity Mirror Tea-light Candle: parallel partially mirrored panes of glass create the illusion of multiple candle flames through the physics of reflection and refraction. ➡️ Follow the link in my profile for info on where to get this and many other amazing items featured here on @physicsfun #physics #physicstoy #refraction #tealight #mirror #infinitymirror #portal #reflection #optics #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 20 9:04上午 PST 张贴
▼5. 这一片板子是能呈现温度差异的液晶，当手印上去之后，可以清楚看到残留的温度变化。
Thermochromic Chiral Liquid Crystals: the thin layer changes color as the molecules of the liquid crystal change orientation and spacing during the phase transition from liquid (warm) to crystal (cool). ➡️Follow the link in my profile for info on where to get this and many other items featured here on @physicsfun #liquidcrystal #physics #physicstoy #Exploratorium #phase #phasetransition #chiral #science #thermometer #braggdiffraction #diffraction #interference #solidstate #chemistry #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 18 12:19下午 PST 张贴
▼6. 温度的变化可以影响许多事情，当导线末端的这个磁铁被加到所谓的「居礼温度」时，磁性就会降为零（这个温度取决于物质的化学成分和晶体结构）；但只要稍微远离冷却，磁性就会恢复，因此只要保持热源供应，这块磁铁就会持续摆动。
Curie Point Heat Engine: when the magnet on the end of the wire heats up to a particular temperature (the Curie point) its magnetic field is temporarily lost until it cools. The engine design uses a second magnet to pull the swinging magnet back into the heat source once the magnetic field is reestablished. Repetition of this process creates mechanical motion as long as the heat source is fueled. ➡️ Follow the link in my profile for info on where to get this and many of the amazing devices featured here on @physicsfun #PierreCurie #curiepoint #magnetism #magnets #magneticfield #heat #heatengine #physics #physicstoy #candle #neodymium #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 19 9:30上午 PST 张贴
▼7. 艺术跟物理学并不一定是背道而驰的两门学科，艺术家Francois Dallegret就以压刻力层板夹住了这5000颗不鏽钢球，但这些球体会自然产生一些变化，有些地方空了出来，有些球则因为静电在顶部漂浮。
Atomix: art and model of crystal structure and mathematical packing problems. Created by artist Francois Dallegret from acrylic and 5000 stainless steel spheres. Crystallographic defects such as vacancies and planar discontinuities can be created. Some spheres float at the top due to static charge. ➡️ Follow the link in my profile for info on how to obtain many of the amazing items featured here on @physicsfun #art #atomix #crystallographic #mathtoy #physics #physicstoy #packing #packingproblem #science #cannonballproblem #lattice #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 16 9:46上午 PST 张贴
▼8. 一个对称轴能带给立方体有趣的改变，当握住它旋转时，这个立方体可以转动超过1分钟以上。（影片为简短版本）
Cube Top: symmetry axes are often associated with interesting physics. For instance- a cube can spin like a top. This stainless steel top was produced in the studio of @kyleskinetics and can spin for more than a minute. The final half second shown here in 250 fps, watch with sound on for best effect. ➡️ Follow the link in my profile for info on how to obtain many of the amazing items featured here on @physicsfun #spin #spinningtop #cube #physics #physicstoy #top #symmetry #axis #rotation #rotationalinertia #moment #stability #curious #kyleskinetics #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 11 11:56上午 PST 张贴
▼9. 小小的蜡烛就可以做出一个蒸汽引擎！在这小台的蒸汽机下，只要点燃蜡烛，上面的飞轮就可以快速运转。蒸汽的发明实在很聪明啊！
Tea Candle Steam Engine: a functional piston steam engine complete with boiler and flywheel. Takes about 2 minutes to get going after the candle is lit. The invention that powered the industrial revolution on a desktop! Made by Wilesco. ➡️ Follow the link in my profile for info on where to get this and many other items featured here on @physicsfun #physics #physicstoy #heatengine #steamengine #thermodynamics #candle #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 9 9:28上午 PST 张贴
▼10. 当一个沙漏被包在水柱中时，会发生什幺事情呢？在水柱被倒转之后，沙漏的沙子开始往下倾泻，这时候玻璃的中心会开始变化，并缓慢开始上升。
Floating Hourglass Puzzle: famous physics puzzle- why does the hourglass not start rising right away? The glass only ascends after about half of the sand has transferred to the lower bulb. The hourglass is a normal glass timer, it is submersed in plain water, and the main tube has an inner diameter which is at least 2mm larger than the diameter of the glass. A simple physics property of the hourglass changes and explains this behavior. I'll post the answer in a few days. ANSWER: As the sand moves from top to bottom the center of mass of the glass changes. Initially the glass is top heavy and wedges against the walls of the cylinder where friction holds it down. Thanks for all the thoughtful and creative comments! ➡️ Follow the link in my profile for info on where to get a version of this physics puzzle and many of the amazing items featured here on @physicsfun #physics #physicstoy #physicspuzzle #puzzle #buoyancy #hourglass #float #gravity #torque #force #friction #science #scienceisawesome #floatinghourglass physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 10 11:16上午 PST 张贴
▼11. 来看看三颗玻璃球能带给我们什幺惊喜。事实上这三颗玻璃球内蕴含了些许的氧化铀，所以在紫色雷射笔照射下，便会散发出绿色的光芒！当然我们都知道铀是放射性物质，但这样微量的铀并没有风险。
Uranium Glass Marbles: the very small quantities of uranium oxide in this glass give it its green color and produces brilliant fluorescence under a 405nm violet laser pointer. Uranium is of course radioactive but the tiny amount in this kind of glass poses no risk. The florescence has nothing to do with the radioactivity- in fact it is myth that radioactive items glow! ➡️ Follow the link in my profile for info on where to buy this and many other items featured here on @physicsfun #uranium #uraniumglass #uraniummarble #marble #laser #405nm #laserpointer #violet #physicstoy #physics #glass #radioactive #giegercounter #science #UV #ultraviolet #glow #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 8 8:33上午 PST 张贴
▼12. 一个磁针的陀螺跟一个迴纹针就可以来玩这个把戏，当迴纹针碰触到陀针尖端时，就会因为牛顿第三运动和转惯动量持续运动。
Paperclip Magnetic Top: the magnetic tipped top attaches to the perimeter of the paperclip- but since the top has much more mass, the paperclip is put into curious motion due to Newton's 3rd law and the top's rotational inertia. This transparent version allows full view of the moving clip. Patented in 1946 under the name Hoy-Poy Top, this antique kinetic art toy made it into my collection as a gift from the folks at @shirepostmint- thanks! ➡️ Follow the link in my profile for info on where to get tops like this one and many other physics toys featured here on @physicsfun #top #spinningtop #vintagetoy #newtons3rdlaw #physics #physicstoy #angularmomentum #relativemotion #magneticfield #magnetic #kineticart #science #centerofmass #magnetictop #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 7 8:29上午 PST 张贴
▼13. 延续着前面电池、磁铁与铜线圈的奇妙关係，当你把铜线圈挂上两极装着磁铁的电池时，一部小小的电动机便出现了！
Self Propelled Homopolar Motor: cylindrical neodymium magnets supply the static magnetic field for this motor and become the wheels of a very simple vehicle with an AA battery as the energy source. As soon as both ends of the copper wire make contact an electric current will flow which in turn induces a magnetic field around the wire. This induced field around the copper wire will then interact with the neodymium magnets on each end causing them to spin- a wonderful example of a motor with minimal components. ➡️ Follow the link in my profile for info about where to get this and other items featured here on @physicsfun #homopolar #motor #homopolarmotor #physics #physicstoy #electromagnetism #magnets #neodymium #ampereslaw #electromagnet #current #copper #selfpropelled #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 5 10:19上午 PDT 张贴
▼14. 有没有觉得这骰子实在长得很奇怪？事实上它就跟一般的骰子一样，骰起来是完全公平的。原因就是它的每一面都跟另外一面对称。
Skew Dice: these unusually shaped dice are completely fair- roll them and the probability of outcomes are identical to a standard set of dice! The odd shapes are a special type of polyhedra called asymmetric trigonal trapezohedra which come in right and left handed versions- this set has one of each (mirror images of each other). What allows this shape to be fair like a cube has to do with the property of being isohedral, where each face of an object will map onto all other faces via a symmetry of the object. Manufactured by The Dice Lab. ➡️ Follow the link in my profile for info about where to get these and many other items featured here on @physicsfun #mathtoy #geometry #physics #physicstoy #fairdice #isohedral #polyhedra #skewdice #trigonal #probability #mirrorsymmetric #trapezohedron #dice #science #mathstoy physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 3 11:16上午 PDT 张贴
▼15. 这个瓶子里装的不是一般的水，而是水和酒精的混合物，其中金色的正是铁磁流体；当磁性物直靠近时，这个流体就会因为磁力和表面张力等产生有趣变化。（莫名疗癒啊！）
physicsfun（@physicsfun）张贴的影片 于 2016 年 11月 月 1 8:44上午 PDT 张贴
▼16. 橡皮筋连接了这两颗球体，当它被缠绕在一起时，旋转惯性会让它自动恢复原状。
Centripetal Spheres: two ball bearings connected by a rubber band orbit each other as energy oscillates between elastic potential energy and rotation kinetic energy. Just wind up the rubber band and let go. When the rubber band has unwound the rotational inertia of bearings winds it back up until it changes direction. ➡️ Follow the link in my profile for info on where to get the supplies to make your own. #centripetal #physics #physicstoy #kinetic #kineticenergy #kineticart #elastic #elasticenergy #ballbearings #sphere #rotationalkineticenergy #angularmomentum #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 10月 月 26 9:25上午 PDT 张贴
▼17. 这是一个独特的动力模型，当用不同方向、力度旋转时，它会呈现截然不同的变化。谁说物理模型就不能是一件艺术品？
The Helicone: an interactive kinetic sculpture designed by John Edmark and distributed by playableArt. With a bit of practice I finally mastered the transformation in both directions: A snap of the wrist imparts angular momentum to the laser cut wood petals which then rotate until an internal mechanism stops their motion with predetermined spacing- a helix transforms to an abstract pine cone. A second snap of the wrist in the opposite direction returns the helix. ➡️ Follow the link in my profile for info on where to get this and many other items featured here on @physicsfun #kineticart #angularmomentum #physicstoy #physics #rotation #rotationalinertia #art #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 10月 月 18 8:57上午 PDT 张贴
▼18. 大家小时候有没有做过这样的实验呢？只要在马蹄铁上方放下铁屑，就可以清楚观察到它的「磁力」，让它变成有形的运动！
Iron Filings in Silicone Oil Suspension: visualizing the invisible- the magnetic field lines around a horseshoe magnet. In the presence of a magnetic field, ferromagnetic materials (such as iron) temporarily become magnets. Here the iron filings become dipole magnets and link up and align like tiny compass needles to follow and reveal the magnetic field lines associated with the permanent magnet underneath. Viscous silicone oil temporarily keeps the iron particles suspended yet allows for rotation and repositioning under the influence of the magnetic field. ➡️ Follow the link in my profile for info on where to obtain this device and many other items featured here on @physicsfun #physics #magnetic #magnetism #magneticfield #physicstoy #dipole #dipolefield #demonstration #silicone #physicsdemo #horseshoemagnet #electromagnetism #science #scienceisawesome physicsfun（@physicsfun）张贴的影片 于 2016 年 10月 月 13 11:11上午 PDT 张贴
