Question

A 180 μF defibrillator capacitor is charged to 1500 V. When fired through a patient's chest, it loses 95% of its charge in 40 ms. What is the resistance of the person's chest?

Answer 1

The resistance of the person's chest is approximately 0.222 Ω.

Step-by-step explanation:

The resistance of the person's chest can be calculated using the formula for an RC circuit:

R = (t / C) * ln(V1 / V2)

where R is the resistance, t is the time constant, C is the capacitance, V1 is the initial voltage, and V2 is the final voltage.

Given that the time constant is 40 ms, the capacitance is 180 μF, the initial voltage is 1500 V, and the final voltage is 5% of the initial voltage (0.05 * 1500 V), we can substitute these values into the formula:

R = (40 ms / 180 μF) * ln(1500 V / 0.05 * 1500 V)

Simplifying the equation gives:

R ≈ 0.222 Ω