P Performance MattersWelcome, Bertiana!► ||A Tools -Question 2 of 51Submit Test04.CFE.2003380.2003390.2003836.2003840.Phy...A cell phone will typically have a power output of 1.4 watts when playing a song that lasts for 300 seconds. If the electrical resistance of the cellphone is 400 Q, what is the totalcharge needed to play the song?

Answered: ong that lasts for 300 seconds. If the…

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ong that lasts for 300 seconds. If the electrical resis

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 55P: A 20.00-V battery is used to supply current to a 10-k resistor. Assume the voltage drop across any...

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A flashing lamp in a Christmas earring is based on an RC discharge of a capacitor through its resistance. The effective duration of the flash is 0.250 s, during which it produces an average 0.500 W from an average 3.00 V. (a) What energy does it dissipate? (b) How much charge moves through the lamp? (c) Find the capacitance, (d) What is the resistance of the lamp? (Since average values are given for some quantities, the shape of the pulse profile is not needed.)
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An ECG monitor must have an KC time constant lessthan 1.00102s to be able to measure variations involtage oversmall time intervals, (a) If the resistance of the circuit (duemostly to that of the patient's chest) is 1.00kTwhat is the maximum capacitance of the circuit?(b) Would It be difficult in practice to limit the capacitance to less than the value found in (a)?
A lightbulb is connected to a variable power supply. As the potential across the bulb is varied, the resulting current and the filaments temperature are measured. The data are listed in Table P28.38. a. Find R for each entry in Table P28.38, and then plot R as a function of T. b. Assume that room temperature is at 293 K. Find R0 (resistance at room temperature). Comment on your result.
Figure P27.48 shows a circuit model for the transmission of an electrical signal such as cable TV to a large number of subscribers. Each subscriber connects a load resistance RL between the transmission line and the ground. The ground is assumed to be at zero potential and able to carry any current between any ground connections with negligible resistance. The resistance of the transmission line between the connection points of different subscribers is modeled as the constant resistance RT. Show that the equivalent resistance across the signal source is Req=12[(4RTRL+RT2)1/2+RT] Suggestion: Because the number of subscribers is large, the equivalent resistance would not change noticeably if the first subscriber canceled the service. Consequently, the equivalent resistance of the section of the circuit to the right of the first load resistor is nearly equal to Req. Figure P27.48
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For 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 P27.14