High School Math Phys SMILE Meeting
20 April 1999
Notes prepared by Alex Junievicz

Bill Blunk [Joliet Central High School, retired]

He brought in a sheet that reveals the magnetic fields and showed with a magnetic field sheet display that the levitron base has a magnetic field that basically has a hole in the center.

FJ Schaal [Hi Tech Low Tech Lane Tech High School]

He first placed a grid on the board by using the chart that has the holes to allow chalk dust to produce a grid. He placed points (2,13) and (16,3) on the grid and used the formula

Dist = Sqrt[(x1-x2)2+(y1-y2)2]

He explained the steps and keys to press on the calculator: ( ( 2 -18 ) ( 2 + ( 13 -3 ) ( 2 ) ( = distance Now adding an additional point of (-12,-6), using the above formula we get distances:

Sqrt(356) = 18.868
Sqrt(981) = 31.320
Sqrt(557) = 23.601

Hero [HERON] formula for the area of a triangle of sides a, b, c:

Area = Sqrt(s(s-a)(s-b)(s-c))
where s =(a+b+c/2

This gives 224 [exactly!!], whereas by graphing and counting the number of fully enclosed squares plus 1/2 the number of partially enclosed squares we get 219

Karlene Joseph [Lane Tech High School]

She brought in an article from 4-11 Chicago Sun Times with questions about Baseball and Physics. Distance difference of approximately 3 feet further for every increase of 10oF, the orientation so the sun will not be in front of the batter and a wind of 10 mph can change the distance a ball travels in 400 feet by 30 feet. [Strange, but True by Bill and Rich Stones]

Porter Commented about changes in the game. The "spitball" was banned in 1920. Also, before 1920 only one baseball was used in a game, and it just got dirtier and dirtier. In 1921 the umpire was given the option to replace the balls when it became too Schmutzig [Deutsch: filthy]. (the average life of a ball today in the major leagues is 7 pitches); Distances were shortened for more home runs; Orientation of the wind. And, of course, the "strike zone" has shrunk dramatically over the years.

Larry Alofs [Kenwood High School]

Space Pendulum revisited.
He tried to explain some of seemingly perpetual (SP) devices that have rotating magnets that are activated by electronics

The coils are loosely wrapped around an iron rod so that they can be slid on and off so that the correct orientation of the coil can be determined by trial and error. The PVC pipe is hung so that it can swing with the cow magnet about 0.5cm above the top of the coil. The 12V auto tail light bulb is the circuit to protect the transistor in case something goes wrong.

Arlyn Van Ek [Iliana Christian High School]

He tried to show the effects of different power light bulbs in a parallel and series circuit.
With different wattage, why is the larger wattage (lower resistance) dimmer when in series, yet brighter when in parallel?? A way of explaining is to use V=I R to solve for the unknown. If V is fixed [parallel] we solve for I, whereas if I if the same we solve for V.

It was pointed out that when the wattage was close the higher wattage bulb would gain brightness more slowly than the brighter one. This is because a Tungsten bulb has a lower resistance when cold, thus the higher resistance would get a surge while the lower resistance (large wattage) would take longer...A flicker of brightness surge in the lower wattage. (Edison's original bulbs had carbon filaments and had the reverse where it would slowly get bright, where tungsten would cause a surge to quickly get to brightness. Why do bulbs burn out when they are turned on ???)

Other matters

A Tobecksen [Richard Vocational High School]

He brought in Cuisenair "Pattern Block Puzzles" by having groups work together solving. The problem utilizes Co-Op Learning.

The problem is to take blocks of various shapes and colors and make a specified figure.