What is the voltage across C_{2} in the circuit of Figure 12-48?
What is the voltage across C_{2} in the circuit of Figure 12-48?
The reactance of the individual capacitors and the total reactance were determined in Example 12-18. Substituting into Equation 12-28 : V_{\chi }= \left(\frac{V_{C\chi }}{X_{C(tot)}} \right) V_{s}.
V_{2 }= \left(\frac{V_{C2 }}{X_{C(tot)}} \right) V_{s}= \left(\frac{468 \ \Omega }{3.65 \ k\Omega } \right)10 \ V= 1.28 \ VNotice that the voltage across the larger capacitor is the smaller fraction of the total. You can obtain the same result from Equation 12-12 : V_{\chi }= \left(\frac{C_{T }}{C_{\chi }} \right) V_{T}.
V_{2 }= \left(\frac{C_{T }}{C_{2 }} \right) V_{s}= \left(\frac{0.0087 \ \mu F }{0.068 \ \mu F } \right)10 \ V= 1.28 \ V