University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 26, Problem 26.88PP
Cell membranes across a wide variety of organisms have a capacitance per unit area of 1 µF/cm2. For the electrical signal in a nerve to propagate down the axon, the charge on the membrane “capacitor” must change. What time constant is required when the ion channels are open? (a) 1 µs; (b) 10 µs; (c) 100 µs; (d) 1 ms.
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Chapter 26 Solutions
University Physics (14th Edition)
Ch. 26 - In which 120-V light bulb does the filament have...Ch. 26 - Two 120-V light bulbs, one 25-W and one 200-W,...Ch. 26 - You connect a number of identical light bulbs to a...Ch. 26 - In the circuit shown in Fig. Q26.4, three...Ch. 26 - If two resistors R1 and R2 (R2 R1) are connected...Ch. 26 - If two resistors R1 and R2 (R2 R1) are connected...Ch. 26 - A battery with no internal resistance is connected...Ch. 26 - A resistor consists of three identical metal...Ch. 26 - A light bulb is connected in the circuit shown in...Ch. 26 - A real battery, having nonnegligible internal...
Ch. 26 - If the battery in Discussion Question Q26.10 is...Ch. 26 - Consider the circuit shown in Fig. Q26.12. What...Ch. 26 - Is it possible to connect resistors together in a...Ch. 26 - The battery in the circuit shown in Fig. Q26.14...Ch. 26 - In a two-cell flashlight, the batteries are...Ch. 26 - Identical light bulbs A, B, and C are connected as...Ch. 26 - The emf of a flashlight battery is roughly...Ch. 26 - Will the capacitors in the circuits shown in Fig....Ch. 26 - Verify that the time constant RC has units of...Ch. 26 - For very large resistances it is easy to construct...Ch. 26 - When a capacitor, battery, and resistor are...Ch. 26 - A uniform wire of resistance R is cut into three...Ch. 26 - A machine part has a resistor X protruding from an...Ch. 26 - A resistor with R1 = 25.0 is connected to a...Ch. 26 - A 42- resistor and a 20- resistor are connected in...Ch. 26 - A triangular array of resistors is shown in Fig....Ch. 26 - For the circuit shown in Fig. E26.6 both meters...Ch. 26 - For the circuit shown in Fig. E26.7 find the...Ch. 26 - Three resistors having resistances of 1.60 , 2.40...Ch. 26 - Now the three resistors of Exercise 26.8 are...Ch. 26 - Power Rating of a Resistor. The power rating of a...Ch. 26 - In Fig. E26.11, R1, = 3.00 , R2 = 6.00 , and R3=...Ch. 26 - In Fig. E26.11 the battery has emf 35.0 V and...Ch. 26 - Compute the equivalent resistance of the network...Ch. 26 - Compute the equivalent resistance of the network...Ch. 26 - In the circuit of Fig. E26.15, each resistor...Ch. 26 - Consider the circuit shown in Fig. E26.16. The...Ch. 26 - In the circuit shown in Fig. E26.17, the voltage...Ch. 26 - In the circuit shown in Fig. E26.18, = 36.0 V,...Ch. 26 - CP In the circuit in Fig. E26.19, a 20.0- resistor...Ch. 26 - In the circuit shown in Fig. E26.20, the rate at...Ch. 26 - Light Bulbs in Series and in Parallel. Two light...Ch. 26 - Light Bulbs in Series. A 60-W, 120-V light bulb...Ch. 26 - In the circuit shown in Fig. E26.23, ammeter A1...Ch. 26 - The batteries shown in the circuit in Fig. E26.24...Ch. 26 - In the circuit shown in Fig. E26.25 find (a) the...Ch. 26 - Find the emfs 1 and 2 in the circuit of Fig....Ch. 26 - In the circuit shown in Fig. E26.27, find (a) the...Ch. 26 - In the circuit shown in Fig. E26.28, find (a) the...Ch. 26 - The 10.00-V battery in Fig. E26.28 is removed from...Ch. 26 - The 5.00-V battery in Fig. E26.28 is removed from...Ch. 26 - In the circuit shown in Fig. E26.31 the batteries...Ch. 26 - In the circuit shown in Fig. E26.32 both batteries...Ch. 26 - In the circuit shown in Fig. E26.33 all meters are...Ch. 26 - In the circuit shown in Fig. E26.34, the 6.0-...Ch. 26 - The resistance of a galvanometer coil is 25.0 ,...Ch. 26 - The resistance of the coil of a pivoted coil...Ch. 26 - A circuit consists of a series combination of...Ch. 26 - A galvanometer having a resistance of 25.0 has a...Ch. 26 - A capacitor is charged to a potential of 12.0 V...Ch. 26 - You connect a battery, resistor, and capacitor as...Ch. 26 - A 4.60-F capacitor that is initially uncharged is...Ch. 26 - You connect a battery, resistor, and capacitor as...Ch. 26 - CP In the circuit shown in Fig. E26.43 both...Ch. 26 - A 12.4-F capacitor is connected through a 0.895-M...Ch. 26 - An emf source with = 120 V, a resistor with R =...Ch. 26 - A resistor and a capacitor are connected in series...Ch. 26 - CP In the circuit shown in Fig. E26.47 each...Ch. 26 - A 1.50-F capacitor is charging through a 12.0-...Ch. 26 - In the circuit in Fig. E26.49 the capacitors are...Ch. 26 - A 12.0-F capacitor is charged to a potential of...Ch. 26 - In the circuit shown in Fig. E26.51, C = 5.90 F, ...Ch. 26 - Prob. 26.52ECh. 26 - A 1500-W electric beater is plugged into the...Ch. 26 - In Fig. P26.54, the battery has negligible...Ch. 26 - The two identical light bulbs in Example 26.2...Ch. 26 - Each of the three resistors in Fig. P26.56 has a...Ch. 26 - (a) Find the potential of point a with respect to...Ch. 26 - CP For the circuit shown in Fig. P26.58 a 20.0-...Ch. 26 - Calculate the three currents I1, I2, and I3...Ch. 26 - What must the emf in Fig. P26.60 be in order for...Ch. 26 - Find the current through each of the three...Ch. 26 - (a) Find the current through the battery and each...Ch. 26 - Consider the circuit shown in Fig. P26.63. (a)...Ch. 26 - In the circuit shown in Fig. P26.64, = 24.0 V,...Ch. 26 - In the circuit shown in Fig. P26.65, the current...Ch. 26 - In the circuit shown in Fig. P26.66 all the...Ch. 26 - Figure P26.67 employs a convention often used in...Ch. 26 - Three identical resistors are connected in series....Ch. 26 - A resistor R1 consumes electrical power P1 when...Ch. 26 - The capacitor in Fig. F26.70 is initially...Ch. 26 - A 2.00-F capacitor that is initially uncharged is...Ch. 26 - A 6.00-F capacitor that is initially uncharged is...Ch. 26 - Point a in Fig. P26.73 is maintained at a constant...Ch. 26 - The Wheatstone Bridge. The circuit shown in Fig....Ch. 26 - (See Problem 26.67.) (a) What is the potential of...Ch. 26 - A 2.36-F capacitor that is initially uncharged is...Ch. 26 - A 224- resistor and a 589- resistor are connected...Ch. 26 - A resistor with R = 850 is connected to the...Ch. 26 - A capacitor that is initially uncharged is...Ch. 26 - DATA You set up the circuit shown in Fig. 26.22a,...Ch. 26 - DATA You set up the circuit shown in Fig. 26.20....Ch. 26 - DATA The electronics supply company where you work...Ch. 26 - An Infinite Network. As shown in Fig. P26.83, a...Ch. 26 - Suppose a resistor R lies along each edge of a...Ch. 26 - BIO Attenuator Chains and Axons. The infinite...Ch. 26 - Assume that a typical open ion channel spanning an...Ch. 26 - In a simple model of an axon conducting a nerve...Ch. 26 - Cell membranes across a wide variety of organisms...
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- Assume a length of axon membrane of about 0.10 m is excited by an action potential (length excited = nerve speed pulse duration = 50.0 m/s 2.0 103 s = 0.10 m). In the resting state, the outer surface of the axon wall is charged positively with K+ ions and the inner wall has an equal and opposite charge of negative organic ions, as shown in Figure P18.43. Model the axon as a parallel-plate capacitor and take C = 0A/d and Q = C V to investigate the charge as follows. Use typical values for a cylindrical axon of cell wall thickness d = 1.0 108 m, axon radius r = 1.0 101 m, and cell-wall dielectric constant = 3.0. (a) Calculate the positive charge on the outside of a 0.10-m piece of axon when it is not conducting an electric pulse. How many K+ ions are on the outside of the axon assuming an initial potential difference of 7.0 102 V? Is this a large charge per unit area? Hint: Calculate the charge per unit area in terms of electronic charge e per squared (2). An atom has a cross section of about 1 2 (1 = 1010 m). (b) How much positive charge must flow through the cell membrane to reach the excited state of + 3.0 102 V from the resting state of 7.0 102 V? How many sodium ions (Na+) is this? (c) If it takes 2.0 ms for the Na+ ions to enter the axon, what is the average current in the axon wall in this process? (d) How much energy does it take to raise the potential of the inner axon wall to + 3.0 102 V, starting from the resting potential of 7.0 102 V? Figure P18.43 Problem 43 and 44.arrow_forwardConsider the circuit shown in Figure P20.52, where C1 = 6.00 F, C2 = 3.00 F, and V = 20.0 V. Capacitor C1 is first charged by closing switch S1. Switch S1 is then opened, and the charged capacitor is connected to the uncharged capacitor by closing S2. Calculate (a) the initial charge acquired by C1 and (b) the final charge on each capacitor. Figure P20.52arrow_forwardA pair of capacitors with capacitances CA = 3.70 F and CB = 6.40 F are connected in a network. What is the equivalent capacitance of the pair of capacitors if they are connected a. in parallel and b. in series?arrow_forward
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