173 lines
6.4 KiB
HTML
173 lines
6.4 KiB
HTML
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<!DOCTYPE html PUBLIC "-//w3c//dtd html 4.0 transitional//en">
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html;
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charset=windows-1252">
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<meta name="GENERATOR" content="Mozilla/4.7 [en] (X11; U; OSF1 V4.0
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alpha) [Netscape]">
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<meta name="Author" content="C. L. Davis">
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<title>Magnetism - Self Inductance - Physics 299</title>
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<meta content="C. L. Davis" name="author">
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<body style="color: rgb(0, 0, 0); background-color: rgb(255, 255,
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255);" link="#0000ee" vlink="#551a8b" alink="#ff0000">
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<center>
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<h1> <img src="ULPhys1.gif" height="50" width="189"
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align="texttop"></h1>
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</center>
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<center>
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<h1>Self Inductance<br>
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</h1>
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</center>
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<center><img src="celticbar.gif" height="22" width="576"><br>
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<br>
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<font color="#ff0000"><i>
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</i></font><font color="#ff0000"><i>
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</i></font>
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<div class="copy-paste-block"><font color="#ff0000"><i><span
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class="bqQuoteLink">"A</span></i></font><font
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color="#ff0000"><i><span class="bqQuoteLink"> fact is a simple
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statement that everyone believes. It is innocent,
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unless found guilty. A hypothesis is a novel
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suggestion that no one wants to believe. It is
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guilty, until found effective</span></i><span></span>"</font><br>
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</div>
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<font color="#ff0000"><i> </i><font color="#000000">Edward Teller</font></font><br>
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</center>
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<img src="netbar.gif" height="40" width="100%" align="middle">
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<blockquote> </blockquote>
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<ul>
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<li><img alt="magselfindfig1" src="mag_selfind_fig1.gif"
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height="298" width="446" align="right">Consider now a single
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coil/circuit/loop with N turns. As the current in the loop
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changes the magnetic field and hence the magnetic flux through
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the loop changes. This changing "self flux" through
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Faraday's Law leads to and induced emf in the circuit,</li>
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</ul>
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<div align="center"><img alt="magselfindeqn1"
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src="mag_selfind_eqn1.jpg" height="73" width="154"><br>
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<div align="left">
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<ul>
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<li>In the same manner as mutual inductance we define the self
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inductance of the circuit, L, as follows</li>
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</ul>
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<div align="center"><img alt="magselfindeqn2"
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src="mag_selfind_eqn2.jpg" height="42" width="143"><br>
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<blockquote>
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<div align="left">so that the induced emf - sometimes called
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a <i><b>"back emf"</b></i> - is given by<br>
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<div align="center"><img alt="magselfindeqn3"
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src="mag_selfind_eqn3.jpg" height="81" width="149"><br>
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<div align="left">This "back emf" always opposes the
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primary emf (due to Lenz's Law), as shown in the
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diagram at right.<br>
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</div>
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</div>
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</div>
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</blockquote>
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<div align="left"><img alt="hot" src="hot.gif" height="43"
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width="79"> From above, <img alt="magselfindeqn4"
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src="mag_selfind_eqn4.jpg" height="76" width="148"
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align="middle"> which can be compared to the similar
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equation for capacitance <img alt="magselfindeqn5"
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src="mag_selfind_eqn5.jpg" height="77" width="138"
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align="middle"> .<br>
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<ul>
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<li>Calculating self inductance proceeds by the same steps
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as mutual inductance - Calculate <b>B</b>, calculate
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magnetic flux, then use the second equation above to
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determine L.<br>
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</li>
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</ul>
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<ol>
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<blockquote>
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</blockquote>
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<blockquote> </blockquote>
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</div>
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<div align="center"><img src="netbar.gif" height="40" width="100%"></div>
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<div align="center">
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<div align="center"> </div>
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<center>
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<p style="color: rgb(255, 0, 0); font-style: italic;"
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class="MsoNormal">
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</p>
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<font color="#ff0000"><i>This girl said she recognized me from
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the vegetarian club, but I'd never met herbivore. </i></font><br>
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<br>
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<img src="celticbar.gif" height="22" width="576"> <br>
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<p><i>Dr. C. L. Davis</i> <br>
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<i>Physics Department</i> <br>
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<i>University of Louisville</i> <br>
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<i>email</i>: <a href="mailto:c.l.davis@louisville.edu">c.l.davis@louisville.edu</a>
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<br>
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</p>
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<p><img src="header-index.gif" height="51" width="92"> </p>
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</center>
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<blockquote> </blockquote>
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</html>
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