141 lines
5.2 KiB
HTML
141 lines
5.2 KiB
HTML
<!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>Electricity - Series and Parallel Circuits - Physics 299</title>
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<meta content="C. L. Davis" name="author">
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</head>
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<body style="color: rgb(0, 0, 0); background-color: rgb(255, 255,
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255);" link="#0000ee" alink="#ff0000" vlink="#551a8b">
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<center>
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<h1> <img src="ULPhys1.gif" height="50" align="texttop"
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width="189"></h1>
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</center>
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<center>
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<h1>Series and Parallel Circuits<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>"</i></font><font color="#ff0000"><i> </i></font><font
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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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It would be better for the true physics if there were no
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mathematicians on earth." <br>
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</i><font color="#000000">Daniel Bernoulli</font></font><br>
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</center>
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<img src="netbar.gif" height="40" align="middle" width="100%"> <br>
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<ul>
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<li>You may already be familiar with the idea of circuits with
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resistors in series or parallel or some combination of the two.</li>
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</ul>
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<ul>
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<ul>
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<li>
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<h3><font color="#3333ff">Series</font></h3>
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</li>
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</ul>
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</ul>
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<blockquote>
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<blockquote><img alt="fig1" src="elec_circuits_fig1.jpg"
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height="168" align="right" width="273">The same current flows
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in each resistor, the voltages across them are typically
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different, where V = V<sub>1</sub> + V<sub>2</sub> + V<sub>3</sub>
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which leads to the equivalent resistance formula<br>
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<br>
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<div align="center">R<sub>eq</sub> = R<sub>1</sub> + R<sub>2</sub>
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+ R<sub>3</sub><br>
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</div>
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</blockquote>
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</blockquote>
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<div align="left">
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<ul>
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<ul>
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<li>
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<h3><font color="#3333ff">Parallel</font></h3>
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</li>
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</ul>
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</ul>
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<blockquote>
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<blockquote>The potential difference across each resistor is the
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same, but the currents through them are typically different,
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where I = I<sub>1</sub> + I<sub>2</sub> + I<sub>3</sub>.
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This lead to the equivalent resistance formula,<br>
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<div align="center"><img alt="eqn1"
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src="elec_circuits_eqn1.jpg" height="58" width="152"><br>
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<br>
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<div align="left">Note that both of the diagrams below
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represent resistors in parallel.<br>
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</div>
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</div>
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<img alt="fig2" src="elec_circuits_fig2.jpg" height="173"
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width="312">
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<img alt="fig3" src="elec_circuits_fig3.jpg" height="179"
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width="301"><br>
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<br>
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</blockquote>
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</blockquote>
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<ul>
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<ul>
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<li>
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<h3><font color="#3333ff">Combinations</font></h3>
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</li>
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</ul>
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</ul>
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<blockquote>
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<blockquote>Some circuits can be analysed as combinations of
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series and parallel circuits. In the circuit below R<sub>2</sub>
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and R<sub>3</sub> are in parallel, their equivalent resistance
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is then in series with R<sub>1</sub>.<br>
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<div align="center"><img alt="fig4"
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src="elec_circuits_fig4.jpg" height="181" width="390"><br>
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</div>
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</blockquote>
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<img alt="exclamation" src="exclamation-icon.gif" height="30"
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width="31"> Note that it is not possible to represent all
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circuits as combinations of series and parallel elements, this
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is most obvious in many cases where there is more than one
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battery in the circuit, see example below. To analyse this
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type of circuit we must use Kirchhoff's Laws.<br>
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<br>
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<div align="center"><img alt="fig5" src="elec_circuits_fig5.jpg"
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height="185" width="435"><br>
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</div>
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<div align="center"><br>
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</div>
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<blockquote>
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<div align="center"> </div>
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</blockquote>
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</blockquote>
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</div>
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<img src="netbar.gif" height="40" width="100%">
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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>Got mole problems? Call Avogadro at
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602-1023.</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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<p><br>
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</p>
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</body>
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</html>
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