What would be a good science fair project? [Archive]

Uncle Al

Sep19-04, 06:56 AM

<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>\n\nTimeTraveler wrote:\n>\n> I need a good science fair project for ISR (independent scienc\n> research). I\'m a high school senior and have already taken AP Physics\n> (my favorite), AP Chemistry, and AP Biology and currently taking ISR. I\n> need something thats doable by a high school student and preferably\n> wouldn\'t cost me more than \\$300\n\nFairly small bore Pyrex or acrylic tube. Not iron! Thin cylindrical\nmagnets poled along their long axes. Coils of magnet wire of\nappropriate wound length vs. magnets\' length and thickness vs. their\ndiameter and length appropriately spaced along the tube.\nLED/photocell gap at entrance and beyond exit of each coil. Paired\ncapacitor networks or other power supply to pulse discharge high\ncurrent through each coil vs. impedence and inductance re time\nconstant.\n\nSnap magnet down tube bore to first coil. Light beam is interrupted.\nCoil flash energizes N to S pole of magnet. Magnet gets sucked in and\naccelerates. It breaks the next light beam after exiting the coil,\nwhich flashes energizes again, oppositely, and repels the magnet away,\naccelerating it more. Do that few times and the exiting magnet will\nhave enough muzzle velocity to blast through a half-inch inch of\nplywood. BTW, impact often fragments the magnet to shrapnel. Google\n"linear accelerators" and "drift tubes."\n\nCall it the "Really Big Particle Accelerator." You will have to be\nclever with relays to engineer magnetic field strength, duration, and\ndirection with large enough current flows and not fry your power\nsupply with t the back pulse.\n\nOr look through old back issues of "Scientific American" that contain\nStong\'s "Amateur Scientist" and pick something exotic.\n\n--\nUncle Al\nhttp://www.mazepath.com/uncleal/\n(Toxic URL! Unsafe for children and most mammals)\nhttp://www.mazepath.com/uncleal/qz.pdf\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">  View this Usenet post in original ASCII form </a></div><P></jabberwocky>TimeTraveler wrote:
>
> I need a good science fair project for ISR (independent scienc
> research). I'm a high school senior and have already taken AP Physics
> (my favorite), AP Chemistry, and AP Biology and currently taking ISR. I
> need something thats doable by a high school student and preferably
> wouldn't cost me more than $300

Fairly small bore Pyrex or acrylic tube. Not iron! Thin cylindrical
magnets poled along their long axes. Coils of magnet wire of
appropriate wound length vs. magnets' length and thickness vs. their
diameter and length appropriately spaced along the tube.
LED/photocell gap at entrance and beyond exit of each coil. Paired
capacitor networks or other power supply to pulse discharge high
current through each coil vs. impedence and inductance re time
constant.

Snap magnet down tube bore to first coil. Light beam is interrupted.
Coil flash energizes N to S pole of magnet. Magnet gets sucked in and
accelerates. It breaks the next light beam after exiting the coil,
which flashes energizes again, oppositely, and repels the magnet away,
accelerating it more. Do that few times and the exiting magnet will
have enough muzzle velocity to blast through a half-inch inch of
plywood. BTW, impact often fragments the magnet to shrapnel. Google
"linear accelerators" and "drift tubes."

Call it the "Really Big Particle Accelerator." You will have to be
clever with relays to engineer magnetic field strength, duration, and
direction with large enough current flows and not fry your power
supply with t the back pulse.

Or look through old back issues of "Scientific American" that contain
Stong's "Amateur Scientist" and pick something exotic.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf