Principles of Physics: A Calculus-Based Text
5th Edition
ISBN: 9781133104261
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 21, Problem 73P
A battery has an emf ε and internal resistance r. A variable load resistor R is connected across the terminals of the battery. (a) Determine the value of R such that the potential difference across the terminals is a maximum. (b) Determine the value of R so that the current in the circuit is a maximum. (c) Determine the value of R so that the power delivered to the load resistor is a maximum. Choosing the load resistance for maximum power transfer is a case of what is called impedance matching in general. Impedance matching is important in shifting gears on a bicycle, in connecting a loudspeaker to an audio amplifier, in connecting a battery charger to a bank of solar photoelectric cells, and in many other applications.
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Chapter 21 Solutions
Principles of Physics: A Calculus-Based Text
Ch. 21.1 - Consider positive and negative charges moving...Ch. 21.2 - Prob. 21.2QQCh. 21.2 - When does an incandescent lightbulb carry more...Ch. 21.5 - For the two incandescent lightbulbs shown in...Ch. 21.7 - Prob. 21.5QQCh. 21.7 - With the switch in the circuit of Figure 21.18a...Ch. 21.7 - Prob. 21.7QQCh. 21.9 - Consider the circuit in Figure 21.29 and assume...Ch. 21 - If the terminals of a battery with zero internal...Ch. 21 - Wire B has twice the length and twice the radius...
Ch. 21 - The current-versus-voltage behavior of a certain...Ch. 21 - Prob. 4OQCh. 21 - A potential difference of 1.00 V is maintained...Ch. 21 - Prob. 6OQCh. 21 - A metal wire of resistance R is cut into three...Ch. 21 - The terminals of a battery are connected across...Ch. 21 - Prob. 9OQCh. 21 - Two conducting wires A and B of the same length...Ch. 21 - When resistors with different resistances are...Ch. 21 - When operating on a 120-V circuit, an electric...Ch. 21 - Prob. 13OQCh. 21 - Prob. 14OQCh. 21 - In the circuit shown in Figure OQ21.15, each...Ch. 21 - Prob. 1CQCh. 21 - Prob. 2CQCh. 21 - Prob. 3CQCh. 21 - Referring to Figure CQ21.4, describe what happens...Ch. 21 - When the potential difference across a certain...Ch. 21 - Use the atomic theory of matter to explain why the...Ch. 21 - Prob. 7CQCh. 21 - (a) What advantage does 120-V operation offer over...Ch. 21 - Prob. 9CQCh. 21 - Prob. 10CQCh. 21 - If you were to design an electric heater using...Ch. 21 - Prob. 12CQCh. 21 - Prob. 13CQCh. 21 - Prob. 14CQCh. 21 - Why is it possible for a bird to sit on a...Ch. 21 - Prob. 1PCh. 21 - Prob. 2PCh. 21 - The quantity of charge q (in coulombs) that has...Ch. 21 - Prob. 4PCh. 21 - Prob. 5PCh. 21 - Figure P21.6 represents a section of a conductor...Ch. 21 - Prob. 7PCh. 21 - A 0.900-V potential difference is maintained...Ch. 21 - Prob. 9PCh. 21 - A lightbulb has a resistance of 240 when...Ch. 21 - Prob. 11PCh. 21 - Prob. 12PCh. 21 - While taking photographs in Death Valley on a day...Ch. 21 - Prob. 14PCh. 21 - If the current carried by a conductor is doubled,...Ch. 21 - Prob. 16PCh. 21 - Prob. 17PCh. 21 - Prob. 18PCh. 21 - Prob. 19PCh. 21 - Prob. 20PCh. 21 - Prob. 21PCh. 21 - Prob. 22PCh. 21 - Prob. 23PCh. 21 - Prob. 24PCh. 21 - A 100-W lightbulb connected to a 120-V source...Ch. 21 - Prob. 26PCh. 21 - Prob. 27PCh. 21 - Prob. 28PCh. 21 - A toaster is rated at 600 W when connected to a...Ch. 21 - Prob. 30PCh. 21 - Prob. 31PCh. 21 - Review. A well-insulated electric water heater...Ch. 21 - A battery has an emf of 15.0 V. The terminal...Ch. 21 - Two 1.50-V batterieswith their positive terminals...Ch. 21 - An automobile battery has an emf of 12.6 V and an...Ch. 21 - Prob. 36PCh. 21 - Prob. 37PCh. 21 - Prob. 38PCh. 21 - Consider the circuit shown in Figure P21.39. Find...Ch. 21 - Four resistors are connected to a battery as shown...Ch. 21 - Three 100- resistors are connected as shown in...Ch. 21 - Prob. 42PCh. 21 - Calculate the power delivered to each resistor in...Ch. 21 - Prob. 44PCh. 21 - The ammeter shown in Figure P21.45 reads 2.00 A....Ch. 21 - Prob. 46PCh. 21 - The circuit shown in Figure P21.47 is connected...Ch. 21 - In Figure P21.47, show how to add just enough...Ch. 21 - Taking R = 1.00 k and = 250 V in Figure P21.49,...Ch. 21 - For the circuit shown in Figure P21.50, we wish to...Ch. 21 - In the circuit of Figure P21.51, determine (a) the...Ch. 21 - Jumper cables are connected from a fresh battery...Ch. 21 - Prob. 53PCh. 21 - Prob. 54PCh. 21 - Prob. 55PCh. 21 - Prob. 56PCh. 21 - In the circuit of Figure P21.57, the switch S has...Ch. 21 - Prob. 58PCh. 21 - The circuit in Figure P21.59 has been connected...Ch. 21 - Assume that global lightning on the Earth...Ch. 21 - Prob. 61PCh. 21 - Prob. 62PCh. 21 - Prob. 63PCh. 21 - Prob. 64PCh. 21 - Prob. 65PCh. 21 - An oceanographer is studying how the ion...Ch. 21 - The values of the components in a simple series RC...Ch. 21 - Prob. 68PCh. 21 - Prob. 69PCh. 21 - Prob. 70PCh. 21 - The student engineer of a campus radio station...Ch. 21 - Prob. 72PCh. 21 - A battery has an emf and internal resistance r. A...Ch. 21 - Prob. 74PCh. 21 - Prob. 75PCh. 21 - Prob. 76PCh. 21 - Prob. 77P
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