Faraday's Experiment: Estimating Pulse Duration & Magnitude

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The discussion focuses on estimating the pulse duration and magnitude of current in Faraday's galvanometer experiment, which involved coils made of 203 feet of copper wire. The setup includes a battery of 100 plates, with the wire diameter specified as 1/20 inch, but lacks details on the wooden block's dimensions and the number of turns in the coil. Participants are attempting to verify equations related to voltage, current, and inductance, while also considering the inductance formulas for air core coils. One user has derived a differential equation but is uncertain about the next steps in the calculation process. The conversation emphasizes the need for further exploration of inductance and coil characteristics to complete the analysis.
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Homework Statement



The coils which first produced a slight but detectable kick in Faraday's galvanometer he describes as made of 203 feet of copper wire each, wound around a large block of wood. The turns of the second spiral (that is, single layer coil) were interposed between those of the first, but separated from them by twine. The diameter of the copper wire itself was 1/20 inch. He does not give the dimensions of the wooden block or the number of turns in the coil. In the experiment, one of these coils was connected to a "battery of 100 plates." (Assume, that one plate is roughly 1 volt.) See if you can make a rough estimate of the duration in seconds (it will be small) and magnitude in amperes of the pulse of current that passed through the galvanometer.

Homework Equations





The Attempt at a Solution



If someone could verify these:

V - I1R - LI1' - MI2' = 0 and
0-I2R - LI2' + MI1' = 0 and M = L

Some from there I added the two equations and assuming that I1 = V/R(1-e^(-R/L)t) I plugged that in and solved the differential equation for which I got I2 = V/R(2-e^(-R/L)t

and then I'm at a loss form what to do...
 
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Perhaps you are supposed to look at inductance formulae for air core coils, involving wire diameter, number of turns/inch, and diameter of former?
 
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