13.9B: The Schering Bridge
- Page ID
- 5852
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This bridge can be used for measuring capacitance.
FIGURE \(\text{XIII.10}\)
The admittance of the fourth arm is \(\frac{1}{R_4}+jC_4\omega\), and its impedance is the reciprocal of this. I leave the reader to balance the bridge and to show that
\[\tag{13.9.6}\frac{R_1}{R_2}=\frac{C_4}{C_3}\]
and
\[\tag{13.9.7}C_1=\frac{C_3R_4}{R_2}.\]