COLLEGE PHYSICS
2nd Edition
ISBN: 9781711470832
Author: OpenStax
Publisher: XANEDU
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Textbook Question
Chapter 21, Problem 31CQ
The RC time constant in heart defibrillation is crucial to limiting the time the current flows. If the capacitance in the defibrillation unit is fixed, how would you manipulate resistance in the circuit to adjust the RC constant t? Would an adjustment of the applied voltage also be needed to ensure that the current delivered has an appropriate value?
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An ECG monitor must have a time constant less than 100 microsecond to be able to measure variations in voltage over small time intervals. If the resistance of the circuit (due mostly to that of the patient’s chest) is 1000 Ohms, what is the maximum capacitance of the circuit? Please submit your answer in units of nanoFarad (nF).
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Figure
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Calculate the heart rate in beats per minute for R = 200 kn and C = 5.0 μF, if the capacitor discharges when its voltage
reaches 80% of the source voltage Vs.
Express your answer in beats per minute to three significant figures.
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Chapter 21 Solutions
COLLEGE PHYSICS
Ch. 21 - Prob. 1CQCh. 21 - Prob. 2CQCh. 21 - Prob. 3CQCh. 21 - Prob. 4CQCh. 21 - Prob. 5CQCh. 21 - Knowing that the severity of a shock depends on...Ch. 21 - Would your headlights dim when you start your...Ch. 21 - Some strings of holiday lights are wired in series...Ch. 21 - If two household lightbulbs rated 60 W and 100 W...Ch. 21 - Suppose you are doing a physics lab that asks you...
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