The average resistivity of the human body (apart from surface resistance of the skin) is about 5.0 Ω · m. The
a. What is the resistance between the hands if the skin resistance is negligible?
b. If skin resistance is negligible, what potential difference between the hands is needed for a lethal shock current of 100 mA? Your result shows that even small potential differences can produce dangerous currents when skin is damp.
Want to see the full answer?
Check out a sample textbook solutionChapter 22 Solutions
College Physics: A Strategic Approach (4th Edition)
Additional Science Textbook Solutions
The Cosmic Perspective
University Physics Volume 1
Essential University Physics: Volume 2 (3rd Edition)
College Physics
College Physics (10th Edition)
Physics for Scientists and Engineers with Modern Physics
- Two 1.50-V batterieswith their positive terminals in the same directionare inserted in series into a flashlight. One battery has an internal resistance of 0.255 , and the other has an internal resistance of 0.153 . When the switch is closed, the bulb carries a current of 600 mA. (a) What is the bulbs resistance? (b) What fraction of the chemical energy transformed appears as internal energy in the batteries?arrow_forwardThe resistance between terminals a and b in Figure P27.36 is 75.0 . If the resistors labeled R have the same value, determine R. Figure P27.36arrow_forwardA 10.00-meter long wire cable that is made of copper has a resistance of 0.051 ohms, (a) What is the weight if the wire was made of copper? (b) What is the weight of a 10.00-meter-long wire of the same gauge made of aluminum? (c)What is the resistance of the aluminum wire? The density of copper is 8960 kg/m3 and the density of aluminum is 2760 kg/m3.arrow_forward
- A battery has an emf of 15.0 V. The terminal voltage of the battery is 11.6 V when it is delivering 20.0 W of power to an external load resistor R. (a) What is the value of R? (b) What is the internal resistance of the battery?arrow_forwardFour resistors are connected to a battery as shown in Figure P27.15. (a) Determine the potential difference across each resistor in terms of . (b) Determine the current in each resistor in terms of I. (c) What If? If R3 is increased, explain what happens to the current in each of the resistors. (d) In the limit that R3 , what are the new values of the current in each resistor in terms of I, the original current in the battery? Figure P27.15arrow_forwardIn the circuit of Figure P27.20, the current I1 = 3.00 A and the values of for the ideal battery and R are unknown. What are the currents (a) I2 and (b) I3? (c) Can you find the values of and R? If so, find their values. If not, explain. Figure P27.20arrow_forward
- (a) During surgery, a current as small as 20.0 ? applied directly to the heart may cause ventricular fibrillation. If the resistance of the exposed heart is 300 , what is the smallest voltage that poses this danger? (b) Does your answer imply that special electrical safety precautions are needed?arrow_forward(a) During surgery, a current as small as 20.0A applied directly to the heart may cause ventricular fibrillation. If the resistance of the exposed heart is 300 what is the smallest voltage that poses thisdanger? (b) Does your answer imply that special electrical safetyprecautions are needed?arrow_forwardA Figure P29.35 shows a combination of six resistors with identical resistance R. What is the equivalent resistance between points a and b?arrow_forward
- (a) Can the circuit shown in Figure P27.21 be reduced to a single resistor connected to a battery? Explain. Calculate the currents (b) I1, (c) I2, and (d) I3. Figure P27.21arrow_forwardTwo resistors, one having a resistance of 900k are connected in series to produce a total resistance of 0.500M . (a) What is the value of the second resistance? (b) What is unreasonable about this result? (c) Which assumptions are unreasonable or inconsistent?arrow_forwardFor the purpose of measuring the electric resistance of shoes through the body of the wearer standing on a metal ground plate, the American National Standards Institute (ANSI) specifies the circuit shown in Figure P27.14. The potential difference V across the 1.00-M resistor is measured with an ideal voltmeter. (a) Show that the resistance of the footwear is Rshoes=50.0VVV (b) In a medical test, a current through the human body should not exceed 150 A. Can the current delivered by the ANSI-specified circuit exceed 150 A? To decide, consider a person standing barefoot on the ground plate. Figure P27.14arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningCollege PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax College