2. In the 2010 film Inception, there is a scene in which Eames uses a defibrillator to resuscitate Fischer's heart and deliver the needed kick to pull Cobb and Ariadne out of a dream again, trying to avoid a spoiler a little bit. A defibrillator is actually a very simple device that consists of an RC circuit powered by a DC source. When the circuit is in one position, the capacitor in the defibrillator charges, doing so with a time constant T. When the defibrillator is used, the capacitor discharges with a time constant T, through the patient's body, which acts as a resistor (as shown). The optimal capacitance in a defibrillator circuit is C = 60 F and the human heart has an impedance of Z = 40. The pulse delivered by the defibrillator will discharge 95% of the charge stored. The charging of the defibrillator usually works by means of multiple charging cycles using lithium-ion batteries run through a step-up transformer, but this works like applying a voltage directly with an E = 2000 V DC source. a. How long does it take to deliver the defibrillator pulse to the patient? b. In the film, the bunker where Fischer is being defibrillated is in level 3 of the dream, so 10 hours of reality time equates to 10 days of level 3 time. If the defibrillator is charged using the single 2000 V source across a 70 k resistor (and again charges up to 95%), how much "real-world" time does this take?

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