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Ohms Law

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OHM’s Law

Although there are literally thousands of formulas, I only try to remember two: Ohm's Law and the Power Formula. You can deal with most anything built before 1980 (except radio and TV) with these two formulas. The first, Ohm's law, states that E = I x R (Or, electromotive force in volts = intensity in amps, times the resistance). So those of you that are good at math games already know that we can change it to read R = E/I or I = E/R. That first class back in the sixties taught it as a magic circle, with E over I x R and you just took the one you wanted to know out of the circle and did what was left . I.e. If you want to know amps, you take the I out which leaves E/R, so you divide the volts by the resistance to find the amps. The power formula states that P = E x I or Power (in Watts) = Volts times Amps. It can also be remembered as a magic circle.Simply plug the resistance that you measure in to Ohm's Law and solve. More on this later - I’m getting ahead of my self. You may see these written with different symbols, depending upon when a book was written, but this is the way it was taught when my Scout was new. We will get back to formulas later. Now I want to go into electricity’s alter ego. |
Ohm's Law:
E = I x RPower Formula:
P = E x I Magic triangle or circle
(click for full-size view with comments) | Magnetism is the force possessed by some materials which enables them to attract or repel certain other materials. Magnets fall into two broad categories: 'natural', like lodestone, and 'artificial', which are magnetized by outside forces. Artificial magnets may further be classed as 'permanent' and 'temporary'. Permanent magnets are made of iron or an alloy or even a ceramic that retains its magnetism for a long time. Temporary magnets are magnets because they are in contact with a magnet, or were recently in contact with

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