{"id":1454,"date":"2018-08-03T00:02:44","date_gmt":"2018-08-03T00:02:44","guid":{"rendered":"http:\/\/tmfwarszawa.pl\/?page_id=1454"},"modified":"2019-02-09T22:54:21","modified_gmt":"2019-02-09T22:54:21","slug":"zadania-2019-ang","status":"publish","type":"page","link":"https:\/\/tmfwarszawa.pl\/index.php\/zadania-2019-ang\/","title":{"rendered":"Zadania 2019 (ang)"},"content":{"rendered":"<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">1. Invent Yourself<\/span><\/strong><br \/>\nBuild a simple motor whose propulsion is based on corona discharge. Investigate how the rotor&#8217;s motion depends on relevant parameters and optimize your design for maximum speed at a fixed input voltage<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">2.\u00a0Aerosol<\/span><\/strong><br \/>\nWhen water flows through a small aperture, an aerosol may be formed. Investigate the parameters that determine whether an aerosol is formed rather than a jet for example. What are the properties of the aerosol?<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">3. Undertone Sound<\/span><\/strong><br \/>\nAllow a tuning fork or another simple oscillator to vibrate against a sheet of paper with a weak contact between them. The frequency of the resulting sound can have a lower frequency than the tuning fork\u2019s fundamental frequency. Investigate this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">4. Funnel and Ball <\/span><\/strong><br \/>\nA light ball (e.g. ping-pong ball) can be picked up with a funnel by blowing air through it. Explain the phenomenon and investigate the relevant parameters.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">5. Filling Up a Bottle <\/span><\/strong><br \/>\nWhen a vertical water jet enters a bottle, sound may be produced, and, as the bottle is filled up, the properties of the sound may change. Investigate how relevant parameters of the system such as speed and dimensions of the jet, size and shape of the bottle or water temperature affect the sound.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">6. Hurricane Balls <\/span><\/strong><br \/>\nTwo steel balls that are joined together can be spun at incredibly high frequency by first spinning them by hand and then blowing on them through a tube, e.g. a drinking straw. Explain and investigate this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">7. Loud Voices<\/span><\/strong><br \/>\nA simple cone-shaped or horn-shaped object can be used to optimise the transfer of the human voice to a remote listener. Investigate how the resulting acoustic output depends on relevant parameters such as the shape, size, and material of the cone.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">8. Sci-Fi Sound<\/span><\/strong><br \/>\nTapping a helical spring can make a sound like a \u201claser shot\u201d in a science-fiction movie. Investigate and explain this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">9. Soy Sauce Optics<\/span><\/strong><br \/>\nUsing a laser beam passing through a thin layer (about 200 \u00b5m) of soy sauce the thermal lens effect can be observed. Investigate this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">10. Suspended Water Wheel<\/span><\/strong><br \/>\nCarefully place a light object, such as a Styrofoam disk, near the edge of a water jet aiming upwards. Under certain conditions, the object will start to spin while being suspended. Investigate this phenomenon and its stability to external perturbations.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">11. Flat Self-Assembly<\/span><\/strong><br \/>\nPut a number of identical hard regular-shaped particles in a flat layer on top of a vibrating plate. Depending on the number of particles per unit area, they may or may not form an ordered crystal-like structure. Investigate the phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">12. Gyroscope Teslameter<\/span><\/strong><br \/>\nA spinning gyroscope made from a conducting, but nonferromagnetic material slows down when placed in a magnetic field. Investigate how the deceleration depends on relevant parameters.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">13. Moir\u00e9 Thread Counter<\/span><\/strong><br \/>\nWhen a pattern of closely spaced non-intersecting lines (with transparent gaps in between) is overlaid on a piece of woven fabric, characteristic moir\u00e9 fringes may be observed. Design an overlay that allows you to measure the thread count of the fabric. Determine the accuracy for simple fabrics (e.g. linen) and investigate if the method is reliable for more complex fabrics (e.g. denim or Oxford cloth).<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">14. Looping Pendulum<\/span><\/strong><br \/>\nConnect two loads, one heavy and one light, with a string over a horizontal rod and lift up the heavy load by pulling down the light one. Release the light load and it will sweep around the rod, keeping the heavy load from falling to the ground. Investigate this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">15. Newton\u2019s Cradle<\/span><\/strong><br \/>\nThe oscillations of a Newton&#8217;s cradle will gradually decay until the spheres come to rest. Investigate how the rate of decay of a Newton&#8217;s cradle depends on relevant parameters such as the number, material, and alignment of the spheres.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">16. Sinking Bubbles<\/span><\/strong><br \/>\nWhen a container of liquid (e.g. water) oscillates vertically, it is possible that bubbles in the liquid move downwards instead of rising. Investigate this phenomenon.<\/p>\n<p><strong><span id=\"1._Invent_Yourself\" class=\"mw-headline\">17. Popsicle Chain Reaction<\/span><\/strong><br \/>\nWooden popsicle sticks can be joined together by slightly bending each of them so that they interlock in a so-called \u201ccobra weave\u201d chain. When such a chain has one of its ends released, the sticks rapidly dislodge, and a wave front travels along the chain. Investigate the phenomenon.<\/p>\n<p style=\"text-align: right;\"><a href=\"http:\/\/tmfwarszawa.pl\/wp-content\/uploads\/2018\/08\/problems2019_signed.pdf\" target=\"_blank\" rel=\"noopener\">Download pdf<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>1. Invent Yourself Build a simple motor whose propulsion is based on corona discharge. Investigate how the rotor&#8217;s motion depends on relevant parameters and optimize your design for maximum speed at a fixed input voltage 2.\u00a0Aerosol When water flows through a small aperture, an aerosol may be formed. Investigate the parameters that determine whether an [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"class_list":["post-1454","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/P4R8YU-ns","jetpack-related-posts":[],"jetpack_likes_enabled":true,"_links":{"self":[{"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/pages\/1454","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/comments?post=1454"}],"version-history":[{"count":4,"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/pages\/1454\/revisions"}],"predecessor-version":[{"id":1763,"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/pages\/1454\/revisions\/1763"}],"wp:attachment":[{"href":"https:\/\/tmfwarszawa.pl\/index.php\/wp-json\/wp\/v2\/media?parent=1454"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}