A defibrillator uses a capacitor to deliver a large current to a person needing heart stimulation. Assume that the capacitance used is 60microfarads and the resistor it discharges through is 220 ohms. the defibrillator is charged up to 5 kiloVolts and it is discharged through a patient for 1.0 millisecond.(adsbygoogle = window.adsbygoogle || []).push({});

a) What fraction of the time constant is 1.0 millisecond?

b) How much charge is left on the capacitor after the 1.0 millisecond?

c) Find the total charge delivered to the patient.

d) Determine the average current delivered to the patient.'

I used time constant=R*C to find the time constant but it comes out to be smaller than 1.0ms, which does not make sense. I just need to know which equations to use to get the answers right.

Please help. And Thanks to whoever helps!

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Defibrillator discharges. need to find time constant

**Physics Forums | Science Articles, Homework Help, Discussion**