BIO Effect of
The electrical resistance across dry skin is about 100,000 ft Suppose a person with dry skin puts one hand on a 120-V power cord from a home wall socket while the other hand is touching a metal object at 0 V (at what is called ground). Which condition described below is most likely to occur?
a. No sensation
b. Threshold of pain
c. Cannot let go
d. Ventricular fibrillation
e. Severe burns and shock
Want to see the full answer?
Check out a sample textbook solutionChapter 19 Solutions
College Physics
Additional Science Textbook Solutions
Cosmic Perspective Fundamentals
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
College Physics: A Strategic Approach (4th Edition)
The Cosmic Perspective (8th Edition)
University Physics Volume 1
Lecture- Tutorials for Introductory Astronomy
- In places such as hospital operating rooms or factories for electronic circuit boards, electric sparks must be avoided. A prison standing on a grounded floor and touching nothing else can typically have a body capacitance of 150 pF, in parallel with a foot capacitance of 80.0 pF produced by the dielectric soles of his or her shoes. The person acquires static electric charge from interactions with Ills or her surroundings. The static charge flows to ground through the equivalent resistance of the two shoe soles in parallel with each other. A pair of rubber-soled street shoes can present an equivalent resistance of 5.00 103 M. A pair of shoes with special static-dissipative soles can have an equivalent resistance of 1.00 M. Consider the persons body and shoes as forming an RC circuit with the ground. (a) How long does it take the rubber-soled shoes to reduce a persons potential from 3.00 103 V to 100? (b) How long does it take the static-dissipative shoes to do the same thing?arrow_forward(a) Why are fish reasonably safe in an electrical storm? (b) Why are swimmers nonetheless ordered to get out of the water in the same circumstance?arrow_forwardA circuit contains a D-cell battery, a switch, a 20- resistor, and three 20-mF capacitors. The capacitors are connected in parallel, and the parallel connection of capacitors are connected in series with the switch, the resistor and the battery, (a) What is die equivalent capacitance of the circuit? (b) What is the KC time constant? (c) How long before the current decreases to 50% of the initial value once the switch is closed?arrow_forward
- A Van de Graaff generator is one of the original particle accelerators and can be used to accelerate charged particles like protons or electrons. You may have seen it used to make human hair stand on end or produce large sparks. One application of the Van de Graaff generator is to create X-rays by bombarding a hard metal target with the beam. Consider a beam of protons at 1.00 keV and a current of 5.00 mA produced by the generator, (a) What is the speed of the protons? (b) How many protons are produced each second?arrow_forward(a) A defibrillator sends a 6.00-A current through the chest of a patient by applying a 10,000-V potential as in the figure below. What is the resistance of the path? (b) The defibrillator paddles make contact with the patient through a conducting gel that greatly reduces the path resistance. 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. (Hint: The current must be about the same, so a higher voltage would imply greater power. Use this equation for power: P=I2 RP = .)arrow_forward(a) What is the potential difference going from point a to point b in Figure 21.47? (b) What is the potential difference going from c to b? (c) From e to g? (d) From e to d?arrow_forward
- A heart defibrillator being used on a patient has an RC time constant of 10.0 ms due to the resistance of the patient and the capacitance of the defibrillator. (a) If the defibrillator has an 8.00F capacitance, what is the resistance of the path through the patient? (You may neglect the capacitance of the patient and the resistance of the defibrillator.) (b) If the initial voltage is 12.0 kV, how long does it take to decline to 6.00x102 V?arrow_forwardThe- pair of capacitors in Figure P28.63 are fully charged by a 12.0-V battery. The battery is disconnected, and the switch is then closed. Alter 1.00 ms has elapsed, (a) how much charge remains 011 the 3.00-F capacitor? (b) How much charge remains on the 2.00-F capacitor? (c) What is the current in the resistor at this time?arrow_forwardA circuit contains a D cell battery, a switch, a 20- resistor, and four 20-mF capacitors connected in series, (a) What is the equivalent capacitance of the circuit? (b) What is the fiC time constant? (c) How long before the current decreases to 50% of the initial value once the switch is closed?arrow_forward
- Referring to Figure CQ21.4, describe what happens to the light-bulb after the switch is closed. Assume the capacitor has a large capacitance and is initially uncharged. Also assume the light illuminates when connected directly across the battery terminals.arrow_forwardAn oceanographer is studying how the ion concentration in seawater depends on depth. She makes a measurement by lowering into the water a pair of concentric metallic cylinders (Fig. P21.66) at the end of a cable and taking data to determine the resistance between these electrodes as a function of depth. The water between the two cylinders forms a cylindrical shell of inner radius ra, outer radius rb, and length L much larger than rb. The scientist applies a potential difference V between the inner and outer surfaces, producing an outward radial current I. Let represent the resistivity of the water. (a) Find the resistance of the water between the cylinders in terms of L, , ra, an rb. (b) Express the resistivity of the water in terms of the measured quantities L, ra, rb, V, and I. Figure P21.66arrow_forwardYou have a faculty position at a community college and are m (caching a class in automotive technology. You are deep in a discussion of using jumper cables to start a car with a dead battery from a car with a fresh battery. You have drawn the circuit diagram in Figure P27.16 to explain the process. The battery on the left is the live batten- in the correctly functioning car, with emf and internal resistance RL where the L. subscript refers to live. Its terminals are connected directly across those of the dead battery, in the middle of the diagram, with emf and internal resistance RD where the D subscript refers to "dead Then, the starter in the car with the dead battery is activated by closing the ignition switch, allowing the car to start. The resistance of the starter is Rs. A student raises his hand and asks, So is the dead battery being charged while the starter is operating? How do you respond?arrow_forward
- College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningCollege PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax CollegePhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning