College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Textbook Question
Chapter 23, Problem 81GP
Intermittent windshield wipers use a variable resistor in an RC circuit to set the delay between successive passes of the wipers. A typical circuit is shown in Figure P23.78. When the switch closes, the capacitor (initially uncharged) begins to charge and the potential at point b begins to increase. A sensor measures the potential difference between points a and b, triggering a pass of the wipers when Vb = Va. (Another part of the circuit, not shown, discharges the capacitor at this time so that the cycle can start again.)
a. What value of the variable resistor will give 12 seconds from the start of a cycle to a pass of the wipers?
b. To decrease the time, should the variable resistance be increased or decreased?
Figure P23.78
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Chapter 23 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 23 - Prob. 1CQCh. 23 - Prob. 2CQCh. 23 - Current Iin flows into three resistors connected...Ch. 23 - The circuit in Figure Q23.4 has two resistors,...Ch. 23 - The circuit in Figure Q23.5 has a battery and two...Ch. 23 - Prob. 6CQCh. 23 - Prob. 7CQCh. 23 - In the circuit shown in Figure Q23.6, bulbs A and...Ch. 23 - Figure Q23.7 shows two circuits. The two batteries...Ch. 23 - Figure Q23.8 shows two circuits. The two batteries...
Ch. 23 - a. In Figure Q23.9, what fraction of current I...Ch. 23 - Prob. 12CQCh. 23 - Prob. 13CQCh. 23 - Prob. 14CQCh. 23 - Prob. 15CQCh. 23 - Prob. 16CQCh. 23 - Prob. 17CQCh. 23 - Prob. 18CQCh. 23 - Prob. 19CQCh. 23 - Prob. 20CQCh. 23 - Prob. 21CQCh. 23 - Prob. 22CQCh. 23 - Prob. 23CQCh. 23 - Prob. 24CQCh. 23 - Prob. 25CQCh. 23 - Prob. 26CQCh. 23 - Prob. 27CQCh. 23 - Prob. 28CQCh. 23 - Prob. 29CQCh. 23 - A device to make an electrical measurement of skin...Ch. 23 - Consider the model of nerve conduction in...Ch. 23 - Adding a myelin sheath to an axon results in...Ch. 23 - Prob. 34MCQCh. 23 - Prob. 35MCQCh. 23 - Prob. 36MCQCh. 23 - A metal wire of resistance R is cut into two...Ch. 23 - Prob. 38MCQCh. 23 - Prob. 39MCQCh. 23 - If a cells membrane thickness doubles but the cell...Ch. 23 - If a cells diameter is reduced by 50% without...Ch. 23 - Prob. 42MCQCh. 23 - Draw a circuit diagram tor the circuit of Figure...Ch. 23 - Draw a circuit diagram for the circuit of Figure...Ch. 23 - Draw a circuit diagram for the circuit of Figure...Ch. 23 - In Figure P23.4, what is the current in the wire...Ch. 23 - Prob. 5PCh. 23 - Prob. 6PCh. 23 - a. What are the magnitude and direction of the...Ch. 23 - Prob. 8PCh. 23 - The current in a circuit with only one battery is...Ch. 23 - What is the equivalent resistance of each group of...Ch. 23 - What is the equivalent resistance of each group of...Ch. 23 - Prob. 12PCh. 23 - Prob. 13PCh. 23 - You have a collection of 1.0 k resistors. How can...Ch. 23 - You have a collection of six 1.0 k resistors. What...Ch. 23 - You have six 1.0 k resistors. How can you connect...Ch. 23 - Prob. 17PCh. 23 - Prob. 18PCh. 23 - Prob. 19PCh. 23 - Prob. 20PCh. 23 - Prob. 21PCh. 23 - Prob. 22PCh. 23 - Prob. 23PCh. 23 - Prob. 24PCh. 23 - Prob. 25PCh. 23 - Prob. 26PCh. 23 - Prob. 27PCh. 23 - Prob. 28PCh. 23 - Prob. 29PCh. 23 - Prob. 30PCh. 23 - Prob. 31PCh. 23 - Prob. 32PCh. 23 - Prob. 33PCh. 23 - Prob. 34PCh. 23 - Prob. 35PCh. 23 - A 6.0 F capacitor, a 10 F capacitor, and a 16 F...Ch. 23 - A 6.0 F capacitor, a 10 F capacitor, and a 16 F...Ch. 23 - You need a capacitance of 50 F, but you dont...Ch. 23 - You need a capacitance of 50 F, but you dont...Ch. 23 - Prob. 40PCh. 23 - Prob. 41PCh. 23 - Prob. 42PCh. 23 - Prob. 43PCh. 23 - Prob. 44PCh. 23 - Prob. 45PCh. 23 - Prob. 46PCh. 23 - A 10F capacitor initially charged to 20C is...Ch. 23 - A capacitor charging circuit consists of a...Ch. 23 - Prob. 49PCh. 23 - A 9.0-nm-thick cell membrane undergoes an action...Ch. 23 - A cell membrane has a resistance and a capacitance...Ch. 23 - Changing the thickness of the myelin sheath...Ch. 23 - A particular myelinated axon has nodes spaced 0.80...Ch. 23 - To measure signal propagation in a nerve in the...Ch. 23 - A myelinated axon conducts nerve impulses at a...Ch. 23 - Prob. 56GPCh. 23 - Two 75 W (120 V) lightbulbs are wired in series,...Ch. 23 - Prob. 58GPCh. 23 - A real battery is not just an emf. We can If model...Ch. 23 - Prob. 60GPCh. 23 - Batteries are recharged by connecting them to a...Ch. 23 - Prob. 63GPCh. 23 - Prob. 64GPCh. 23 - Prob. 65GPCh. 23 - Prob. 66GPCh. 23 - What is the ratio P parallel/P series of the total...Ch. 23 - You have a device that needs a voltage reference...Ch. 23 - Prob. 69GPCh. 23 - A circuit youre building needs an ammeter that...Ch. 23 - A circuit youre building needs a voltmeter that...Ch. 23 - For the circuit shown in Figure P23.68, find the...Ch. 23 - You have three 12 F capacitors. Draw diagrams...Ch. 23 - Initially, the switch in Figure P23.70 is in...Ch. 23 - Prob. 75GPCh. 23 - Prob. 76GPCh. 23 - Prob. 77GPCh. 23 - Prob. 78GPCh. 23 - Prob. 79GPCh. 23 - Prob. 80GPCh. 23 - Intermittent windshield wipers use a variable...Ch. 23 - Prob. 82GPCh. 23 - In Example 23.14 we estimated the capacitance of...Ch. 23 - The giant axon of a squid is 0.5 mm in diameter,...Ch. 23 - A cell has a 7.0-nm-thick membrane with a total...Ch. 23 - The Defibrillator A defibrillator is designed to...Ch. 23 - The Defibrillator A defibrillator is designed to...Ch. 23 - The Defibrillator A defibrillator is designed to...Ch. 23 - A defibrillator is designed to pass a large...Ch. 23 - The voltage produced by a single nerve or muscle...Ch. 23 - The voltage produced by a single nerve or muscle...Ch. 23 - The voltage produced by a single nerve or muscle...Ch. 23 - The voltage produced by a single nerve or muscle...
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