Chapter 18, Problem 37P

Figure P18.37 shows a simplified model of a cardiac defibrillator, a device used to patients in ventricular fibrillation. When the switch S is toggled to the left, the capacitor C charges through the resistor R .When the switch is toggled to the right, the capacitor discharges current through the patient’s torso, modeled as the resistor R_torso, allowing the heart’s normal rhythm to be reestablished. (a) If the capacitor is initially uncharged with C = 8.00 µF and ε = 1250 V, find the value of R required to charge the capacitor to a voltage of 775 V in 1.50 s. (b) If the capacitor is then discharged across the patient’s torso with, R_torso = 1250 Ω, calculate the voltage across the capacitor after 5.00 ms.

Figure P18.37