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conservative field

integrate around a closed loop

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dielectric

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Polarization P

Polarization charge density p

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GO HAWKS

BEAT

IOWA STATE

Since neither the Packers nor the Bears made the playoff season last year, the management of both teams got together and decided that there should be some sort of post season competition between the two teams because of their great rivalry. They decided on a week long ice fishing competition. The team that caught the most fish at the end of the week would win. So on a cold northern Wisconsin lake they began their contest. The first day, after 8 hours, the Packers had caught 100 fish and the Bears' had 0. At the end of the 2nd day, the Packers had caught 200 fish and the Bears' 0. That evening the Bears' coach got his team together and said, "I suspect some kind of cheating is taking place". So the next morning, he dressed one of his players in green and gold and sent him over to the Packer camp to act as a spy. At the end of the day, he came back to report to the coach. The coach asked, "Well, how about it...are they cheating?" "They sure are" the player reported, "They're cutting holes in the ice!"

Benjamin Franklin

1706-1790

currents

flow of charge convention - direction of flow of positive

charge is direction of current. 1747 - Benjamin Franklin proposes the principle of conservation of charge and calls the fluid that exists and flows “positive”. This educated guess ensures that undergraduates will always be confused about the direction of current flow.

military convention

Average Effects of Continuous ac or dc Electrical Currents on Heart

Electrical Current Biological Effect 1 mA -- -- threshold for feeling 10-20 mA -- -- impossible to

voluntarily let go of the circuit 25 mA -- -- muscle contractions 50-200 mA -- -- ventricular fibrillation

or cardiac arrest

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0414

Gilbert tested many folk tales. Does garlic destroy the magnetic effect of the compass needle? More importantly, he made the first clear distinction between magnetic and the amber effect (staticelectricity, as we call it).

magnetic fields

basic property

NONO magnetic monopoles

N

S S

S

N

N

NO MAGNETIC MONOPOLESDOWN HERE!

We enforce the

“No magnetic monopole”

rule!

magnetic fields • B = 0 Tesla -- Weber/m2

104 Gauss lines / square inch @ ISU B in Iowa City + 0.5 G B in Ames - 0.5 G

NO MAGNETIC MONOPOLES

v

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Universally recognized as a method of facilitating the body's own healing powers, Magnetic Therapy is not entirely a new concept. References to the earliest uses of magnetics to aid the body are recorded in ancient Chinese manuscripts dating back to approximately 2000 B.C. The M+ flexible magnets differ from conventional magnets by utilizing single pole technology. The single pole magnet penetrates deeper and more effectively through soft tissue than a standard magnet configuration.

Bio-Magnetics Universal Holistic HealthTM

One theory behind magnetic healing relies on the magnet's ability to affect the atomic and molecular electro-potential of the blood. Besides containing iron, which is magnetically active, human blood is composed of 90% water. During magnetic therapy, the hydrogen and oxygen molecules in the water as well as iron become magnetically polarized and align with other components in the blood. These charged molecules and aggregates are then able to travel throughout the body more efficiently, thus allowing the blood’s nourishing energy to more effectively support healing and recovery.

earth

opposite poles attract North pole on a

compass is actually a south pole!

continuous magnetic field lines

N

* Turn the compass needle so it is approximately parallel to the wire. * Close the switch to send the current through the wire for about 5-10 seconds. * The compass will align itself with the magnetic field.

B

Ampere’s circuital lawright hand rule

a

I

current ==> magnetic field

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universe

Phony $200 bill passes musterJanuary 31, 2001 DANVILLE, Ky. -- A $200 bill bearing the likeness of President Bush would seem to be an obvious fake. But it seemed real enough to fool one fast-food cashier. Police are looking for the person who used the bill to buy $2.12 worth of food at a Dairy Queen, and drove away after getting $197.88 in change. In addition to the Bush portrait on the front, the treasury seal is marked with the phrase, "The right to bear arms." An oil well appears on the back of the bill. Whoever passed the bill on Jan. 28 could be charged with failure to pay for a purchase, Danville police said. It was such a clear fake that police say it can't be considered a counterfeit.