1. (a) A defibrillator (a device that stores charge on a capacitor used to start the heart beat of a patient under cardiac arrest after suffering irregular heartbeats) sends a 6 A current through the chest of a patient by applying a 7500 V potential as in the figure. What is the resistance of the path (through the wire and the body)? -ai+a R= ΚΩ (b) The defibrillator paddles make contact with the patient through a conducting gel that greatly reduces the path resistance. To understand the importance of using the gel, discuss the difficulties that would ensue if a larger voltage were used to produce the same current through the patient, but with the path having perhaps 50 times the resistance by finding the ratio, Pno-gel Pgel (Hint: The current must be about the same, so a higher voltage would imply greater power. Use this equation for power: P = PR.) What difficulties arise when no gel is used? O a. The voltage is too high for the human body even when the current is the same. O b. There is a risk of skin burns because of the high power deposited.

1. (a) A defibrillator (a device that stores charge on a capacitor used to start the heart beat of a patient under cardiac arrest after suffering irregular heartbeats) sends a 6 A current through the chest of a patient by applying a 7500 V potential as in the figure. What is the resistance of the path (through the wire and the body)? -ai+a R= ΚΩ (b) The defibrillator paddles make contact with the patient through a conducting gel that greatly reduces the path resistance. To understand the importance of using the gel, discuss the difficulties that would ensue if a larger voltage were used to produce the same current through the patient, but with the path having perhaps 50 times the resistance by finding the ratio, Pno-gel Pgel (Hint: The current must be about the same, so a higher voltage would imply greater power. Use this equation for power: P = PR.) What difficulties arise when no gel is used? O a. The voltage is too high for the human body even when the current is the same. O b. There is a risk of skin burns because of the high power deposited.

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter18: Direct-Current Circuits

Section: Chapter Questions

Problem 18P: (a) Find the current in each resistor of Figure P18.18 by using the rules for resistors in series...

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