Current IYPT Crowdsourced References
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Problems
References
The effect of fractal fingering can be observed if a droplet of an ink-alcohol mixture is deposited onto diluted acrylic paint. How are the geometry and dynamics of the fingers influenced by relevant parameters?
I. Phenomenon Demonstration
- R. Camassa, L. Ding, G. McLaughlin, and R. McLaughlin, 74th Annual Meeting of the APS Division of Fluid Dynamics – Gallery of Fluid Motion (2021).
- N. Sharp, FYFD (2022).
II. Books, Encyclopedia, Discussion and Forum Posts
- A. L. Robinson, Science 228, 1077 (1985).
III. Research Papers
- W. Song, N. N. Ramesh, and A. R. Kovscek, Colloids and Surfaces A: Physicochemical and Engineering Aspects 584, 123943 (2020).
- C. W. Park and G. M. Homsy, Physics of Fluids 28, 1583 (1985).
- Canabal, José, et al. Simulation of Dendritic Painting. Computer Graphics Forum 39, 2, 597-606 (2020).
- Lagrée, Bertrand, et al. Scaling properties of viscous fingering (2014).
“A light sphere with a conducting surface is suspended from a thin wire. When the sphere is rotated about its vertical axis (thereby twisting the wire) and then released, it starts to oscillate. Investigate how the presence of a magnetic field affects the motion.”
I. Phenomenon Demonstration
II. Books, Encyclopedia, Discussion and Forum Posts
- https://physics.princeton.edu/~kirkmcd/examples/rotatingsphere.pdf
- https://www.sciencedirect.com/topics/engineering/rotating-magnetic-field
- https://physics.stackexchange.com/questions/521105/torque-on-a-rotating-sphere-in-a-uniform-magnetic-field
III. Research Papers
- E. E. Kriezis, T. D. Tsiboukis, S. M. Panas and J. A. Tegopoulos, “Eddy currents: theory and applications,” in Proceedings of the IEEE, vol. 80, no. 10, pp. 1559-1589, (1992).
- R. C. Youngquist, M. A. Nurge, S. O. Starr, F. A. Leve, and M. Peck, American Journal of Physics 84, 181 (2016).
- M. A. Nurge, R. C. Youngquist, and S. O. Starr, American Journal of Physics 86, 443 (2018).
- R. Hollerbach, R. J. Wiener, I. S. Sullivan, R. J. Donnelly, and C. F. Barenghi, Physics of Fluids 14, 4192 (2002).
- D. V. Redzic, Progress In Electromagnetics Research 110, 383 (2010).
- Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences 199, 413 (1949).
“If you direct an air flow onto a rotating disk with holes, a sound may be heard. Explain this phenomenon and investigate how the sound characteristics depend on the relevant parameters.”
I. Phenomenon Demonstration
- Simple Siren Disc Demonstration //. Homemade Science with Bruce Yeany (YouTube, 2021). https://www.youtube.com/watch?v=-LTtuMj6jZc
- https://soundandscience.de/video/demonstration-disk-siren
- http://berkeleyphysicsdemos.net/node/194%20
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2017). https://en.wikipedia.org/wiki/Siren_disk
- https://sciencedemonstrations.fas.harvard.edu/presentations/siren-discs
- https://www.exploratorium.edu/snacks/siren-disk
- https://www.sciencebuddies.org/stem-activities/build-disk-siren
- https://en.wikipedia.org/wiki/Longitudinal_wave
- https://courses.lumenlearning.com/atd-austincc-physics1/chapter/17-3-sound-intensity-and-sound-level/
- https://pressbooks.pub/sound/chapter/sirens-and-singing-roads/
- https://www.scientificamerican.com/article/building-a-disk-siren/
- T. B. Greenslade, The Physics Teacher 42, 418 (2004).
III. Research Papers
- Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character 98, 414 (1921).
- Regina Collecchia, Dan Somen, and Kevin McElroy. 2014. The Siren Organ. Proceedings of the International Conference on New Interfaces for Musical Expression, Goldsmiths, University of London, pp. 391–394. http://doi.org/10.5281/zenodo.1178732
- Shalash, K., Şahin, F. C., & Schiffmann, J. Non-linear transfer function identification of pressure probes using Siren Disks. Experimental Thermal and Fluid Science, 91, 459–469. (2018).
“When a compact disc or DVD is illuminated with light coming from a filament lamp in such a way that only rays with large angles of incidence are selected, a clear green line can be observed. The colour varies upon slightly changing the angle of the disc. Explain and investigate this phenomenon.”
I. Phenomenon Demonstration
II. Books, Encyclopedia, Discussion and Forum Posts
- https://physics.stackexchange.com/questions/464911/why-do-we-see-a-rainbow-of-colors-reflected-off-a-cd-or-dvd
- H. S. W. Contributors, HowStuffWorks (2000). https://electronics.howstuffworks.com/question52.htm
- C. Nöldeke, The Physics Teacher 28, 484 (1990).
- https://iopscience.iop.org/article/10.1088/0031-9120/28/1/002
- Wikipedia (2022). https://en.wikipedia.org/wiki/Iridescence
- http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/gratcal.html
- https://www.newport.com/n/diffraction-grating-physics
- https://www.thenakedscientists.com/get-naked/experiments/colours-cds
- https://pressbooks.nscc.ca/heatlightsound/chapter/27-4-multiple-slit-diffraction/
- http://panchbhaya.weebly.com/uploads/1/3/7/0/13701351/phys12_c10_10_3.pdf
- https://lup.lub.lu.se/luur/download?func=downloadFile&recordOId=8954105&fileOId=8954108
- https://javalab.org/en/light_interference_on_cd_surface_en/
- https://www.quora.com/Why-does-a-CD-reflect-rainbow-colors/answer/Brad-Moffat-1?ch=10&oid=200189570&share=b554dcef&target_type=answer
- https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_principle
- https://www.physics.louisville.edu/cldavis/phys299/notes/lo_interference.html
- http://www.vikdhillon.staff.shef.ac.uk/teaching/phy217/instruments/phy217_inst_grating.html#:~:text=Since%20the%20angle%20of%20diffraction,distance%20d%20between%20adjacent%20slits
- http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/grating.html
- https://inspiredtobescientist.wordpress.com/2012/05/12/why-do-cds-reflect-rainbow-colors/
- https://www.exploratorium.edu/science_explorer/bub_dome.html#:~:text=Why%20are%20soap%20bubbles%20so,the%20waves%20in%20the%20ocean
III. Research Papers
- Barreiro, J. J., Pons, A., Barreiro, J. C., Castro-Palacio, J. C., & Monsoriu, J. A. Diffraction by electronic components of everyday use. American Journal of Physics, 82(3), 257–261. (2014).
- R. De Luca, M. Di Mauro, O. Fiore, and A. Naddeo, American Journal of Physics 86, 169 (2018).
- Fernández-Dorado, J., Hernández-Andrés, J., Valero, E. M., Nieves, J. L., & Romero, J. A simple experiment to distinguish between replicated and duplicated compact discs using Fraunhofer diffraction. American Journal of Physics, 76(12), 1137–1140. (2008).
- Birriel, J. J. Diffraction by “sheer coincidence”. The Physics Teacher, 56(9), 648–649. (2018).
“When a stream of water hits a rigid metal mesh within a range of angles, a whistling tone may be heard. Investigate how the properties of the mesh, stream and angle affect the characteristics of the sound produced.”
I. Phenomenon Demonstration
- The Humming Tea Filter (YouTube, 2017). https://www.youtube.com/watch?v=-t_sQ5PrRdk
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Whistling
- Wikipedia (2022). https://en.wikipedia.org/wiki/Physics_of_whistles
- Resonances of Open Air Columns. http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/opecol.html#:~:text=Air%20Column%20Resonance,set%20up%20standing%20wave%20patterns
- Wikipedia (2022). https://en.wikipedia.org/wiki/Choked_flow
III. Research Papers
“Secure the lower ends of two identical leaf springs to a non-magnetic base and attach magnets to the upper ends such that they repel and are free to move. Investigate how the movement of the springs depends on relevant parameters.”
I. Phenomenon Demonstration
II. Books, Encyclopedia, Discussion and Forum Posts
- http://pmaweb.caltech.edu/~phy003/labs/mmhohandout3hqM.pdf
- UCSC Physics Demonstration Room. https://ucscphysicsdemo.sites.ucsc.edu/coupled-magnetic-pendulums/
- https://ui.adsabs.harvard.edu/abs/1996AmJPh..64..885M/abstract
- https://boulderschool.yale.edu/sites/default/files/files/suhl_ieee.pdf
- https://patents.google.com/patent/US6035980A/en
III. Research Papers
- I. T. Georgiou and F. Romeo, International Journal of Non-Linear Mechanics 70, 153 (2015).
- G. Donoso, C. L. Ladera, and P. Martín, European Journal of Physics 31, 433 (2010).
- Przybyłowicz, Piotr & Szmidt, Tomasz. Electromagnetic damping of a mechanical harmonic oscillator with the effect of magnetic hysteresis. Journal of Theoretical and Applied Mechanics. 47. 259-273.(2009)
- McCarthy, Lance. On the electromagnetically damped mechanical harmonic oscillator, American Journal of Physics 64, 855 (1996).
- Onorato, P., & De Ambrosis, A. Magnetic damping: Integrating experimental and theoretical analysis. American Journal of Physics, 80(1), 27–35. (2012).
- Sodano, H. A. Eddy Current Damping in Structures. The Shock and Vibration Digest, 36(6), 469–478. (2004).
- Abdullah, Ahn, J.-H., & Kim, H.-Y. Effect of Electromagnetic Damping on System Performance of Voice-Coil Actuator Applied to Balancing-Type Scale. Actuators, 9(1), 8. (2020).
“A droplet of less viscous liquid floating in a bath of a more viscous liquid develops surprising wave-like patterns when the entire system is set into vertical oscillation. Investigate this phenomenon and the parameters relevant to the production of stable patterns.”
I. Phenomenon Demonstration
- Faraday Waves (YouTube, 2015). https://www.youtube.com/watch?v=8HkVDU1ofVQ
- ME312_Lab4: Viscosity and Faraday Waves (2012). https://youtu.be/QKyVg31-Vg8
- APS Physics(2014). https://www.youtube.com/watch?v=OLUZMXuCAxY
- APS Physics (2016). https://www.youtube.com/watch?v=sZzHS2G25dE
II. Books, Encyclopedia, Discussion and Forum Posts
- https://www.physics.utoronto.ca/~phy326/far/far.pdf
- https://www.britannica.com/science/Faraday-effect
- https://en.wikipedia.org/wiki/Faraday_wave
- https://www-users.cse.umn.edu/~vinals/research/fwaves/index.html
III. Research Papers
- M. Durey and P. A. Milewski, Journal of Fluid Mechanics 821, 296 (2017).
- Lau, Y. M., Westerweel, J., & van de Water, W. Using Faraday waves to measure interfacial tension. Langmuir. (2020).
- D. Binks and W. van de Water, Physical Review Letters 78, 4043 (1997).
- Rajchenbach, J., & Clamond, D. (2015). Faraday waves: their dispersion relation, nature of bifurcation and wavenumber selection revisited. Journal of Fluid Mechanics, 777. (2015).
- N. Périnet, D. Juric, and L. S. Tuckerman, Journal of Fluid Mechanics 635, 1 (2009).
- M.-T. Westra, D. J. Binks, and W. Van de Water, Journal of Fluid Mechanics 496, 1 (2003).
- M. Sheldrake, et al. Determinants of Faraday Wave-Patterns in Water Samples Oscillated Vertically at a Range of Frequencies from 50-200 Hz, Water. (2017).
- O. Lioubashevski, J. Fineberg, and L. S. Tuckerman, Physical Review E 55, (1997).
“Take a thick plate of non-magnetic material and fix a neodymium magnet on top of it. Suspend a magnetic rod (which can be assembled from cylindrical neodymium magnets) underneath it. Deflect the rod so that it touches the plate only with highest edge and release it. Study the motion of such a pendulum under various conditions.”
I. Phenomenon Demonstration
- Ludic Science(2016). https://www.youtube.com/watch?v=v0XdcihiSo8
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Eddy_current
- Wikipedia (2022). https://en.wikipedia.org/wiki/Euler%27s_Disk
- Wikipedia (2022). https://en.wikipedia.org/wiki/Magnetoresistance
- Wikipedia (2022). https://en.wikipedia.org/wiki/Hall_effect
- China Ferrite And Neodymium Magnet Manufacturer (Supplier) – Courage Magnet. https://www.dgcourage.com/xinwen/hyxw/318.html
- D. Rantidev, Are Rare Earth Magnets Conductive? https://keepthatshort.com/are-rare-earth-magnets-conductive
- Wikipedia (2022). https://en.wikipedia.org/wiki/Euler%27s_Disk2
- Wikipedia (2022). https://www.real-world-physics-problems.com/eulers-disk
- http://www.eulersdisk.com/physics.html
- https://www.real-world-physics-problems.com/eulers-disk.html
III. Research Papers
- Caps, H., Dorbolo, S., Ponte, S., Croisier, H., & Vandewalle, N. Rolling and slipping motion of Euler’s disk. Physical Review E, 69(5), (2004).
- Stanislavsky, A. A., & Weron, K. Nonlinear oscillations in the rolling motion of Euler’s disk. Physica D: Nonlinear Phenomena, 156(3-4), 247–259, (2001).
“When placed on its side on a ramp and released, a screw may experience growing oscillations as it travels down the ramp. Investigate how the motion of the screw, as well as the growth of these oscillations depend on the relevant parameters.”
I. Phenomenon Demonstration
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2020). https://en.wikipedia.org/wiki/Rolling_cone_motion
- Libretexts, Physics LibreTexts (2020). https://phys.libretexts.org/Bookshelves/Classical_Mechanics/Graduate_Classical_Mechanics_(Fowler)/25%3A_Moments_of_Inertia_and_Rolling_Motion/25.02%3A_Analyzing_Rolling_Motion
- David Tong: Classical Dynamics. http://www.damtp.cam.ac.uk/user/tong/dynamics/three.pdf
III. Research Papers
- G. Csernák, Acta Mechanica 230, 2607 (2019).
- S. P. Bhat and N. Crasta, The Journal of the Astronautical Sciences 65, 261 (2018).
“Sprinkle light particles on a water surface. Then allow a water stream to be incident on the surface from a small height. Under certain conditions, the particles may begin to move up the stream. Investigate and explain this phenomenon.“
I. Phenomenon Demonstration
- These Particles Flow Upstream Instead of Down (YouTube, 2020). https://www.youtube.com/watch?v=kIKEG9kSplI
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Upstream_contamination
- COMSOL. https://www.comsol.com/multiphysics/marangoni-effect
- Wikipedia (2022). https://en.wikipedia.org/wiki/Surfactant
III. Research Papers
- S. Bianchini, A. Lage, T. Siu, T. Shinbrot, and E. Altshuler, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, 20130067 (2013).
“A ferrite rod is placed at the bottom end of a vertical tube. Apply an ac voltage, of a frequency of the same order as the natural frequency of the rod, to a fine wire coil wrapped around its lower end. When a ball is placed on top of the rod, it will start to bounce. Explain and investigate this phenomenon.“
I. Phenomenon Demonstration
- Longitudinal Resonance Measurement on New Ferrite Rods (YouTube, 2014). https://www.youtube.com/watch?v=dU0YO_U945c
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Ferrite_core
- E. Notes, Ferrite Rod Antenna – Ferrite Bar Aerial ” Electronics Notes. http://ffsyfz00.com/basics-tutorial-5.html
III. Research Papers
- A. Stadler, 2011 7th International Conference-Workshop Compatibility and Power Electronics (CPE) (2011).
- F. W. Schott, T. F. Tao, and R. A. Freibrun, Journal of Applied Physics 38, 3015 (1967).
- K. P. Ivanov and G. N. Georgiev, Journal of Applied Physics 67, 6529 (1990).
“Take a vessel and pour some granular material into it, for example, rice. If you dip e.g. a spoon into it, then at a certain depth of immersion, you can lift the vessel and contents by holding the spoon. Explain this phenomenon and explore the relevant parameters of the system.“
I. Phenomenon Demonstration
- (YouTube, 2012). https://www.youtube.com/watch?v=_oJ_Kg30ULU
- (YouTube, 2018). https://www.youtube.com/watch?v=tmtoMETbpfc
- (YouTube, 2017). https://www.youtube.com/watch?v=qoGzk9GdnQQ
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Sphere_packing
- Wikipedia (2022). https://en.wikipedia.org/wiki/Close-packing_of_equal_spheres
- Wikipedia (2022). https://en.wikipedia.org/wiki/Packing_problems
- https://archive.lib.msu.edu/crcmath/math/math/s/s561.htm
- Granular Materials. https://web.physics.ucsb.edu/~complex/research/granular.html
III. Research Papers
- S. V. Franklin, Physics Today 65, 70 (2012).
- A. Mehta, G. C. Barker, and J.-M. Luck, Physics Today 62, 40 (2009).
- R. P. Behringer and B. Chakraborty, Reports on Progress in Physics 82, 012601 (2018).
- H. M. Jaeger, S. R. Nagel, and R. P. Behringer, Physics Today 49, 32 (1996).
“A glass tube with a sealed top is filled with water and mounted vertically. The bottom end of the tube is immersed in a beaker of water and a short segment of the tube is heated. Investigate and explain the periodic motion of the water and any vapour bubbles observed.“
I. Phenomenon Demonstration
- (YouTube, 2022). https://www.youtube.com/shorts/rwWUn9Rsd7A
- (Youtube, 2022). https://www.youtube.com/watch?v=VD00BmaRWAU
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Convection
- COMSOL. https://www.comsol.com/model/free-convection-in-a-water-glass-195
III. Research Papers
- C. Paz, M. Conde, J. Porteiro, and M. Concheiro, International Journal of Heat and Mass Transfer 89, 770 (2015).
- A. Surtaev, V. Serdyukov, J. Zhou, A. Pavlenko, and V. Tumanov, International Journal of Heat and Mass Transfer 126, 297 (2018).
- H. TANAKA, S. HATANO, and S. MARUYAMA, TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B 52, 4014 (1986).
- K. Nakamura, H. N. Yoshikawa, Y. Tasaka, and Y. Murai, Journal of Fluid Mechanics 923, (2021).
“A vertical jet can be refracted when passing through an inclined sieve with a fine mesh. Propose a law for such refraction and investigate relevant parameters.”
I. Phenomenon Demonstration
- (YouTube, 2022). https://www.youtube.com/watch?v=6LBgh48lQuo
- (YouTube, 2016). https://www.youtube.com/watch?v=92Psa-bppXk
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Adhesion
III. Research Papers
- Z. Zhao, Y. Peles, and M. K. Jensen, International Journal of Heat and Mass Transfer 63, 445 (2013).
- C.-Y. Hsu, C.-C. Liang, T.-L. Teng, and A.-T. Nguyen, Ocean Engineering 72, 98 (2013).
“Place a few balls in a round container. If you move the container around a vertical axis, the balls can move co-directionally with the movement of the container, or they can move in the opposite direction. Explain this phenomenon and investigate how the direction of movement depends on relevant parameters.”
I. Phenomenon Demonstration
- (YouTube, 2022). https://www.youtube.com/watch?v=qZymQFDiuO0
II. Books, Encyclopedia, Discussion and Forum Posts
- Citizendium. https://en.citizendium.org/wiki/Centrifugal_force
- Wikipedia (2022). https://en.wikipedia.org/wiki/Rigid_body_dynamics#Rigid-body_angular_momentum
- Wikipedia (2022). https://en.wikipedia.org/wiki/Frictional_contact_mechanics
III. Research Papers
- L. M. Lee, J. P. Ryan, Y. Lahini, M. Holmes-Cerfon, and S. M. Rubinstein, Physical Review E 100, (2019).
- D. A. Weitz, Science 303, 968 (2004).
“A piston placed in the open end of a horizontal test tube which has its other end partially filled with steel wool may oscillate when the closed end is heated up. Investigate the phenomenon and determine the efficiency of this engine.“
I. Phenomenon Demonstration
- (YouTube, 2016). https://www.youtube.com/watch?v=owbjLWrC86g
- (YouTube, 2017). https://www.youtube.com/watch?v=BxYe1QBK3BE
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine
III. Research Papers
- C. Olivier, G. Poignand, and G. Pénelet, European Journal of Physics 38, 015101 (2016).
- J. R. Belcher, W. V. Slaton, R. Raspet, H. E. Bass, and J. Lightfoot, The Journal of the Acoustical Society of America 105, 2677 (1999).
“A sand-filled lane results in the dissipation of the kinetic energy of a moving vehicle. What length is necessary for such an arrester bed to entirely stop a passively moving object (e.g. a ball)? What parameters does the length depend on?”
I. Phenomenon Demonstration
- (YouTube, 2016). https://www.youtube.com/watch?v=owbjLWrC86g
- (YouTube, 2017). https://www.youtube.com/watch?v=BxYe1QBK3BE
II. Books, Encyclopedia, Discussion and Forum Posts
- Wikipedia (2022). https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine
III. Research Papers
- https://personal.math.ubc.ca/~njb/Research/rollit.pdf
- Y.-J. Shin, J.-S. Jeong, C.-W. Jun, and J.-H. Sohn, Journal of Mechanical Science and Technology 34, 4537 (2020).
- B. Coutermarsh, Journal of Terramechanics 44, 275 (2007).
- J. Madsen, D. Negrut, A. Reid, A. Seidl, P. Ayers, G. Bozdech, J. Freeman, and J. O’Kins, SAE International Journal of Commercial Vehicles 5, 280 (2012).
- D. Negussey and Y. P. Vaid, Canadian Geotechnical Journal 23, 155 (1986).
- R. P. Behringer, Physics Today 54, 63 (2001).
How we classify references
We classify all references into one of three categories. Category one is phenomenon demonstration, category two is books, encyclopedia, discussion and forum posts and category three is published research papers. The three categories offer different perspectives into the problem and have different levels of academic rigour.
Phenomenon Demonstration
These are commonly videos on platforms like YouTube, Facebook etc. The videos show the phenomenon described in the problem statement or one that is similar. Whether the videos accurately depict the problem statement is up to individual interpretations. These references are often created to demonstrate a physical principle qualitatively. Many lack control of key parameters and thus not suitable for scientific analysis.
Books, Encyclopedia, Discussion and Forum Posts
This category contains references from many sources. The accuracy of information in this category can vary. Textbooks and lecture slides/notes are the most accurate. Other professional books and student thesis are generally accurate. Encyclopedia and forum post answers are only sometimes accurate because the primary source of information is often missing. [citation needed]. Student discussion is not a reliable source of information.
Research Papers
This category only contains articles written to academic standards. Most of the articles in this section are published in peer-reviewed journals. A very small proportion of articles are from arXiv. Note that the articles on arXiv is only a preprint and might not be peer-reviewed. But since these articles are written with academic rigour in mind, the information accuracy is still generally better than encyclopedia and forum posts.
