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Understanding Electricity… A Hair Raising Experience

Understanding Electricity… A Hair Raising Experience. You walk across the rug, reach for the doorknob and..........ZAP!!! You get a shock.

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Understanding Electricity… A Hair Raising Experience

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  1. Understanding Electricity… A Hair Raising Experience

  2. You walk across the rug, reach for the doorknob and..........ZAP!!! You get a shock. Or, you come inside from the cold, pull off your hat and......BOING!!! All your hair stands on end. What is going on here? And why does it only seem to happen in the winter? The answer is: STATIC ELECTRICITY http://www.sciencemadesimple.com/static.html

  3. Law of Conservation of ChargesNeutral Objects and Charged Objects attractand… http://www.sciencemadesimple.com/static.html

  4. Balancing of Charges http://www.sciencemadesimple.com/static.html

  5. So how does this work? http://www.photographersdirect.com/buyers/stockphoto.asp?imageid=65334

  6. Van der Graff (VDG) generator is a machine that continually draws electrons off a large metal dome. The dome thus becomes strongly positively charged once the machine is turned on. http://www.ap.stmarys.ca/demos/content/e_and_m/hair_raising/hair_raising.html

  7. Tesla and his Invention http://www.tb3.com/tesla/

  8. http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/tc.htm

  9. The Tesla coil is a dynamic device. High voltage radio-frequency current is produced at the rate the spark-gap fires. 120 times a second would be typical. Maximum arcs are produced in profusion immediately and continue for as long as the coil is left running. The sparks, poorly visible in strong light, appear quite strong in subdued lighting conditions. The arcs are purplish to whitish depending on whether they are allowed to go to the open air or are drawn to a nearby grounded rod or wire. A ground wire held close produces very intense sparks. The Fine Details… http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/tc.htm

  10. Tesla coils are not harmless toys. One must constantly be watchful of what is touched. It is said that the r.f. current from the coil flows over the surface of the skin, and is therefore not capable of killing. However, it is also known that contacting a high-powered discharge can cause burns and is extremely painful. The primary circuit of the coil is where the true danger lies; plenty of voltage and amperage here. An inadvertant touch of a fully charged primary capacitor, even with the coil *off*, can kill you. Primary voltages run up to 15,000 volts, but the discharger puts out anywhere from a quarter-million to a couple million volts depending on the input power. Safety of Tesla Coils…

  11. Question: How can you make a balloon stick to the wall when only given the balloon? Static Electricity & Balloons

  12. Answer If you charge a balloon by rubbing it on your hair, it picks up extra electrons and has a negative charge. Holding it near a neutral object will make the charges in that object move. If it is a conductor, many electrons move easily to the other side, as far from the balloon as possible. If it is an insulator, the electrons in the atoms and molecules can only move very slightly to one side, away from the balloon. In either case, there are more positive charges closer to the negative balloon. Opposites attract. The balloon sticks. http://www.sciencemadesimple.com/static.html

  13. Step 2: Using dryer sheets What affect will occur if a charged balloon is then rubbed with a dryer sheet? Will it still stick to the wall?

  14. The balloon will not stick to the wall because the dryer sheet removes the extra electrons added to the balloon… Therefore, the balloon is now NEUTRALand will not stick to the wall. What charge must be on the dryer sheets?

  15. Direct Current Electric Circuits http://hyperphysics.phy-astr.gsu.edu/hbase/electric/dccircon.html#c1

  16. Series Circuits In a series circuit, all elements are attached to make one complete path. Here a battery is attached to three lights. http://www.msnucleus.org/membership/html/k-6/as/technology/4/ast4_3a.html

  17. Real life Circuits vs. Schematic Drawings This drawing is a series circuit with a battery ( 3 cells connected in series) and three lights (loads or resistors). http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4a.html

  18. DC Parallel Circuits The following is a parallel circuit. Notice the wires are arranged such that the lights will be in parallel with each other.

  19. Real life Parallel Circuit vs. Schematic Diagram http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4a.html

  20. There are stages to Science Fairs: School Regional Provincial National International All grades can participate and projects are grouped depending on grade and topic Money and scholarships are given out as students progress through the various stages of fairs Science Fairs & Science Olympics http://www.physics.uwo.ca/sfair/sflinks.htm

  21. For examples: http://school.discovery.com/sciencefaircentral/ (separate science fair guides for students, teachers and parents) http://www.scifair.org/ (“ultimate science fair resource – science project help & ideas) http://www.virtualsciencefair.com/ (Canada wide virtual science fair for K-12) More on Science Fairs…

  22. The general idea is that students pursue excellence through science and/or competition. These can be held at a school or regional level. Best site: http://www.physics.uwo.ca/olympics Science Olympics

  23. Welcome to theFirst AnnualSecondary Science Olympics

  24. In pairs, work to build an electromagnet. Materials: 1m of wire, 1 nail, 1 9V battery, and paperclips First Event…The Solo-Electromagnet Competition

  25. Wrap the wire around the nail Attach the ends of the wire to the terminals of the battery Try to pick up as many paperclips with the electromagnet as possible The maximum number of paperclips is your score for this event. Procedure

  26. In pairs, you will build a boat from Aluminum foil and test for buoyancy Materials: 1 15cm x 15cm piece of Aluminum foil, container of water, & washers. Second Event…The Duo-Boat Float

  27. Create a boat from the Aluminum foil Test to see if it floats Add pennies, washers or nails to your boat until it sinks into the water The number of items added to your boat is your score for this event. Procedure

  28. In groups of 2, you will build the tallest possible free standing tower. Materials: 10 straws, 1 sheet of paper, 20cm of tape The Third and Final Event…The Quad-Straw Free Standing Tower

  29. From the materials given, construct the tallest possible tower When all towers are complete, the tallest in the class will receive 100 points, the second tallest will receive 50 points and the third tallest will receive 25 points. Procedure

  30. Solo-Electromagnet: # of paperclips Duo-Boat Float: # of pennies held Quad Straw Free Standing Tower: points Final Score: ____________ Calculating Time… Congratulations!

  31. Thank you for Participating Have a Great Day Prizes will be awarded On Wednesday! 

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