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13.9A: The Owen Bridge

  • Page ID
    5851
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    13.9.png
    FIGURE \(\text{XIII.9}\)

    This bridge can be used for measuring inductance. Note that the unknown inductance is the only inductance in the bridge. Reactance is supplied by the capacitors.

    Equation 13.9.1 in this case becomes

    \[\tag{13.9.2}\frac{R_1}{R_2+jL_2\omega}=\frac{-j/(C_3\omega)}{R_4-j/(C_4\omega)}.\]

    That is,

    \[\tag{13.9.3}R_1R_4-j\frac{R_1}{C_4\omega}=\frac{L_2}{C_3}-j\frac{R_2}{C_3\omega}.\]

    On equating real and imaginary parts separately, we obtain

    \[\tag{13.9.4}L_2=R_1R_4C_3\]

    and

    \[\tag{13.9.5}\frac{R_1}{R_2}=\frac{C_4}{C_3}.\]


    This page titled 13.9A: The Owen Bridge is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jeremy Tatum via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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