Physics for Scientists and Engineers, Technology Update (No access codes included)
9th Edition
ISBN: 9781305116399
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 28, Problem 28.48P
Turn on your desk lamp. Pick up the cord, with your thumb and index finger spanning the width of the cord. (a) Compute an order-of-magnitude estimate for the current in your hand. Assume the conductor inside the lamp cord next to your thumb is at potential ~ 102 V at a typical instant and the conductor next to your index finger is at ground potential (0 V). The resistance of your hand depends strongly on the thickness and the moisture content of the outer layers of your skin. Assume the resistance of your hand between fingertip and thumb tip is ~ 104 Ω. You may model the cord as having rubber insulation. State the other quantities you measure or estimate and their values. Explain your reasoning. (b) Suppose your body is isolated from any other charges or currents. In order-of-magnitude terms, estimate the potential difference between your thumb where it contacts the cord and your finger where it touches the cord.
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Chapter 28 Solutions
Physics for Scientists and Engineers, Technology Update (No access codes included)
Ch. 28 - To maximize the percentage of the power from the...Ch. 28 - With the switch in the circuit of Figure 27.4a...Ch. 28 - With the switch in the circuit of Figure 27.6a...Ch. 28 - Prob. 28.4QQCh. 28 - Consider the circuit in Figure 27.17 and assume...Ch. 28 - Is a circuit breaker wired (a) in series with the...Ch. 28 - A battery has some internal resistance. (i) Clan...Ch. 28 - The terminals of a battery are connected across...Ch. 28 - When operating on a 120-V circuit, an electric...Ch. 28 - If the terminals of a battery with zero internal...
Ch. 28 - Prob. 28.6OQCh. 28 - What is the time constant of the circuit shown in...Ch. 28 - When resistors with different resistances are...Ch. 28 - When resistors with different resistances are...Ch. 28 - The terminals of a battery are connected across...Ch. 28 - Are the two headlights of a car wired (a) in...Ch. 28 - In the circuit shown in Figure OQ28.12, each...Ch. 28 - Prob. 28.13OQCh. 28 - A circuit consists of three identical lamps...Ch. 28 - A series circuit consists of three identical lamps...Ch. 28 - Suppose a parachutist lands on a high-voltage wire...Ch. 28 - A student claims that the second of two lightbulbs...Ch. 28 - Why is ii possible for a bird to sit on a...Ch. 28 - Given three lightbulbs and a battery, sketch as...Ch. 28 - Prob. 28.5CQCh. 28 - Referring to Figure CQ28.6, describe what happens...Ch. 28 - Prob. 28.7CQCh. 28 - (a) What advantage does 120-V operation offer over...Ch. 28 - Prob. 28.9CQCh. 28 - Prob. 28.10CQCh. 28 - A battery has an emf of 15.0 V. The terminal...Ch. 28 - Two 1.50-V batterieswith their positive terminals...Ch. 28 - An automobile battery has an emf of 12.6 V and 171...Ch. 28 - As in Example 27.2, consider a power supply with...Ch. 28 - Three 100- resistors are connected as shown in...Ch. 28 - Prob. 28.6PCh. 28 - What is the equivalent resistance of the...Ch. 28 - Consider the two circuits shown in Figure P27.5 in...Ch. 28 - Consider the circuit shown in Figure P28.9. Find...Ch. 28 - (a) You need a 45- resistor, but the stockroom has...Ch. 28 - A battery with = 6.00 V and no internal...Ch. 28 - A battery with emf and no internal resistance...Ch. 28 - (a) Kind the equivalent resistance between points...Ch. 28 - (a) When the switch S in the circuit of Figure...Ch. 28 - Prob. 28.15PCh. 28 - Four resistors are connected to a battery as shown...Ch. 28 - Consider die combination of resistors shown in...Ch. 28 - For the purpose of measuring the electric...Ch. 28 - Calculate the power delivered to each resistor in...Ch. 28 - Why is the following situation impossible? A...Ch. 28 - Consider the circuit shown in Figure P28.21 on...Ch. 28 - In Figure P28.22, show how to add just enough...Ch. 28 - The circuit shown in Figure P27.17 is connected...Ch. 28 - For the circuit shown in Figure P28.24, calculate...Ch. 28 - What are the expected readings of (a) the ideal...Ch. 28 - The following equations describe an electric...Ch. 28 - Taking R = 1.00 k and = 250 V in Figure P27.19,...Ch. 28 - You have a faculty position at a community college...Ch. 28 - The ammeter shown in Figure P28.29 reads 2.00 A....Ch. 28 - In the circuit of Figure P28.30, determine (a) the...Ch. 28 - Using Kirchhoffs rules, (a) find (he current in...Ch. 28 - In the circuit of Figure P27.20, the current I1 =...Ch. 28 - In Figure P28.33, find (a) the current in each...Ch. 28 - For the circuit shown in Figure P27.22, we wish to...Ch. 28 - Find the potential difference across each resistor...Ch. 28 - (a) Can the circuit shown in Figure P27.21 be...Ch. 28 - An uncharged capacitor and a resistor are...Ch. 28 - Consider a series RC circuit as in Figure P28.38...Ch. 28 - A 2.00-nF capacitor with an initial charge of 5.10...Ch. 28 - A 10.0-F capacitor is charged by a 10.0-V battery...Ch. 28 - In the circuit of Figure P27.25, the switch S has...Ch. 28 - In the circuit of Figure P27.25, the switch S has...Ch. 28 - The circuit in Figure P28.43 has been connected...Ch. 28 - Show that the integral 0e2t/RCdtin Example 27.11...Ch. 28 - A charged capacitor is connected to a resistor and...Ch. 28 - Prob. 28.46PCh. 28 - Prob. 28.47PCh. 28 - Turn on your desk lamp. Pick up the cord, with...Ch. 28 - Assume you have a battery of emf and three...Ch. 28 - Find the equivalent resistance between points a...Ch. 28 - Four 1.50-V AA batteries in series are used to...Ch. 28 - Four resistors are connected in parallel across a...Ch. 28 - The circuit in Figure P27.35 has been connected...Ch. 28 - The circuit in Figure P27.34a consists of three...Ch. 28 - For the circuit shown in Figure P28.55. the ideal...Ch. 28 - The resistance between terminals a and b in Figure...Ch. 28 - (a) Calculate the potential difference between...Ch. 28 - Why is the following situation impossible? A...Ch. 28 - A rechargeable battery has an emf of 13.2 V and an...Ch. 28 - Find (a) the equivalent resistance of the circuit...Ch. 28 - When two unknown resistors are connected in series...Ch. 28 - When two unknown resistors are connected in series...Ch. 28 - The- pair of capacitors in Figure P28.63 are fully...Ch. 28 - A power supply has an open-circuit voltage of 40.0...Ch. 28 - The circuit in Figure P27.41 contains two...Ch. 28 - Two resistors R1 and R2 are in parallel with each...Ch. 28 - Prob. 28.67APCh. 28 - A battery is used to charge a capacitor through a...Ch. 28 - A young man owns a canister vacuum cleaner marked...Ch. 28 - (a) Determine the equilibrium charge on the...Ch. 28 - Switch S shown in Figure P28.71 has been closed...Ch. 28 - Three identical 60.0-W, 120-V lightbulbs are...Ch. 28 - A regular tetrahedron is a pyramid with a...Ch. 28 - An ideal voltmeter connected across a certain...Ch. 28 - In Figure P27.47, suppose the switch has been...Ch. 28 - Figure P27.48 shows a circuit model for the...Ch. 28 - The student engineer of a campus radio station...Ch. 28 - The circuit shown in Figure P28.78 is set up in...Ch. 28 - An electric teakettle has a multiposition switch...Ch. 28 - A voltage V is applied to a series configuration...Ch. 28 - In places such as hospital operating rooms or...Ch. 28 - The switch in Figure P27.51a closes when Vc23Vand...Ch. 28 - The resistor R in Figure P28.83 receives 20.0 W of...
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