 21.1CQ: A switch has a variable resistance that is nearly zero when closed ...
 21.1PE: (a) What is the resistance of ten 275? resistors connected in seri...
 21.2CQ: What is the voltage across the open switch in Figure 21.43?
 21.2PE: (a) What is the resistance of a 1.00×102 ?, a 2.50k? , and a 4.00...
 21.3CQ: There is a voltage across an open switch, such as in Figure 21.43. ...
 21.3PE: What are the largest and smallest resistances you can obtain by con...
 21.4CQ: Why is the power dissipated by a closed switch, such as in Figure 2...
 21.4PE: An 1800W toaster, a 1400W electric frying pan, and a 75W lamp ar...
 21.5CQ: A student in a physics lab mistakenly wired a light bulb, battery, ...
 21.5PE: Your car’s 30.0W headlight and 2.40kW starter are ordinarily conn...
 21.6CQ: Knowing that the severity of a shock depends on the magnitude of th...
 21.6PE: (a) Given a 48.0V battery and 24.0? and 96.0? resistors, find th...
 21.7CQ: Would your headlights dim when you start your car’s engine if the w...
 21.7PE: Referring to the example combining series and parallel circuits and...
 21.8CQ: Some strings of holiday lights are wired in series to save wiring c...
 21.8PE: Referring to Figure 21.6: (a) Calculate P3 and note how it compares...
 21.9CQ: If two household lightbulbs rated 60 W and 100 W are connected in s...
 21.9PE: Refer to Figure 21.7 and the discussion of lights dimming when a he...
 21.10CQ: Suppose you are doing a physics lab that asks you to put a resistor...
 21.10PE: A 240kV power transmission line carrying 5.00×102 A is hung from g...
 21.11CQ: Before World War II, some radios got power through a “resistance co...
 21.11PE: Show that if two resistors R1 and R2 are combined and one is much g...
 21.12CQ: Some light bulbs have three power settings (not including zero), ob...
 21.12PE: Unreasonable Results Two resistors, one having a resistance of 145 ...
 21.13CQ: Is every emf a potential difference? Is every potential difference ...
 21.13PE: Unreasonable Results Two resistors, one having a resistance of 900 ...
 21.14CQ: Explain which battery is doing the charging and which is being char...
 21.14PE: Standard automobile batteries have six leadacid cells in series, c...
 21.15CQ: Given a battery, an assortment of resistors, and a variety of volta...
 21.15PE: Carbonzinc dry cells (sometimes referred to as nonalkaline cells) ...
 21.16CQ: Two different 12V automobile batteries on a store shelf are rated ...
 21.16PE: What is the output voltage of a 3.0000V lithium cell in a digital ...
 21.17CQ: What are the advantages and disadvantages of connecting batteries i...
 21.17PE: (a) What is the terminal voltage of a large 1.54V carbonzinc dry c...
 21.18CQ: Semitractor trucks use four large 12V batteries. The starter syste...
 21.18PE: What is the internal resistance of an automobile battery that has a...
 21.19CQ: Can all of the currents going into the junction in Figure 21.46 be ...
 21.19PE: (a) Find the terminal voltage of a 12.0V motorcycle battery having...
 21.20CQ: Apply the junction rule to junction b in Figure 21.47. Is any new i...
 21.20PE: A car battery with a 12V emf and an internal resistance of 0.050 ?...
 21.21CQ: (a) What is the potential difference going from point a to point b ...
 21.21PE: The hot resistance of a flashlight bulb is 2.30 ? , and it is run b...
 21.22CQ: Apply the loop rule to loop afedcba in Figure 21.47.
 21.22PE: The label on a portable radio recommends the use of rechargeable ni...
 21.23CQ: Apply the loop rule to loops abgefa and cbgedc in Figure 21.47.
 21.23PE: An automobile starter motor has an equivalent resistance of 0.0500 ...
 21.24CQ: Why should you not connect an ammeter directly across a voltage sou...
 21.24PE: A child’s electronic toy is supplied by three 1.58V alkaline cells...
 21.25CQ: Suppose you are using a multimeter (one designed to measure a range...
 21.25PE: (a) What is the internal resistance of a voltage source if its term...
 21.26CQ: Specify the points to which you could connect a voltmeter to measur...
 21.26PE: A person with body resistance between his hands of 10.0 k ? acciden...
 21.27CQ: To measure currents in Figure 21.49, you would replace a wire betwe...
 21.27PE: Electric fish generate current with biological cells called electro...
 21.28CQ: Why can a null measurement be more accurate than one using standard...
 21.28PE: Integrated ConceptsA 12.0V emf automobile battery has a terminal v...
 21.29CQ: If a potentiometer is used to measure cell emfs on the order of a f...
 21.29PE: Unreasonable ResultsA 1.58V alkaline cell with a 0.200? internal ...
 21.30CQ: Regarding the units involved in the relationship ? = RC , verify th...
 21.30PE: Unreasonable Results (a) What is the internal resistance of a 1.54...
 21.31CQ: The RC time constant in heart defibrillation is crucial to limiting...
 21.31PE: Apply the loop rule to loop abcdefgha in Figure 21.25.
 21.32CQ: When making an ECG measurement, it is important to measure voltage ...
 21.32PE: Apply the loop rule to loop aedcba in Figure 21.25.
 21.33CQ: Draw two graphs of charge versus time on a capacitor. Draw one for ...
 21.33PE: Verify the second equation in Example 21.5 by substituting the valu...
 21.34CQ: When charging a capacitor, as discussed in conjunction with Figure ...
 21.34PE: Verify the third equation in Example 21.5 by substituting the value...
 21.35CQ: When discharging a capacitor, as discussed in conjunction with Figu...
 21.35PE: Apply the junction rule at point a in Figure 21.52.
 21.36CQ: Referring to Figure 21.38, draw a graph of potential difference acr...
 21.36PE: Apply the loop rule to loop abcdefghija in Figure 21.52.
 21.37CQ: A long, inexpensive extension cord is connected from inside the hou...
 21.37PE: Apply the loop rule to loop akledcba in Figure 21.52.
 21.38CQ: In Figure 21.41, does the graph indicate the time constant is short...
 21.38PE: Find the currents flowing in the circuit in Figure 21.52. Explicitl...
 21.39CQ: An electronic apparatus may have large capacitors at high voltage i...
 21.39PE: Solve Example 21.5, but use loop abcdefgha instead of loop akledcba...
 21.40PE: Find the currents flowing in the circuit in Figure 21.47.
 21.41PE: Unreasonable Results Consider the circuit in Figure 21.53, and supp...
 21.42PE: What is the sensitivity of the galvanometer (that is, what current ...
 21.43PE: What is the sensitivity of the galvanometer (that is, what current ...
 21.44PE: Find the resistance that must be placed in series with a 25.0? gal...
 21.45PE: Find the resistance that must be placed in series with a 25.0? gal...
 21.46PE: Find the resistance that must be placed in parallel with a 25.0? g...
 21.47PE: Find the resistance that must be placed in parallel with a 25.0? g...
 21.48PE: Find the resistance that must be placed in series with a 10.0? gal...
 21.49PE: Find the resistance that must be placed in parallel with a 10.0? g...
 21.50PE: Suppose you measure the terminal voltage of a 1.585V alkaline cell...
 21.51PE: Suppose you measure the terminal voltage of a 3.200V lithium cell ...
 21.52PE: A certain ammeter has a resistance of 5.00×10?5 ? on its 3.00A sca...
 21.53PE: A 1.00M? voltmeter is placed in parallel with a 75.0k ? resistor ...
 21.54PE: A 0.0200? ammeter is placed in series with a 10.00? resistor in a...
 21.55PE: Unreasonable Results Suppose you have a 40.0? galvanometer with a ...
 21.56PE: Unreasonable Results (a) What resistance would you put in parallel ...
 21.57PE: What is the emfx of a cell being measured in a potentiometer, if th...
 21.58PE: Calculate the emfx of a dry cell for which a potentiometer is balan...
 21.59PE: When an unknown resistance Rx is placed in a Wheatstone bridge, it ...
 21.60PE: To what value must you adjust R3 to balance a Wheatstone bridge, if...
 21.61PE: (a) What is the unknown emfx in a potentiometer that balances when ...
 21.62PE: Suppose you want to measure resistances in the range from 10.0 ? to...
 21.63PE: The timing device in an automobile’s intermittent wiper system is b...
 21.64PE: A heart pacemaker fires 72 times a minute, each time a 25.0nF capa...
 21.65PE: The duration of a photographic flash is related to an RC time const...
 21.66PE: A 2.00 and a 7.50?F capacitor can be connected in series or paral...
 21.67PE: After two time constants, what percentage of the final voltage, emf...
 21.68PE: A 500? resistor, an uncharged 1.50?F capacitor, and a 6.16V emf ...
 21.69PE: A heart defibrillator being used on a patient has an RC time consta...
 21.70PE: An ECG monitor must have an RC time constant less than 1.00×102 ?s ...
 21.71PE: Figure 21.55 shows how a bleeder resistor is used to discharge a ca...
 21.72PE: Using the exact exponential treatment, find how much time is requir...
 21.73PE: Using the exact exponential treatment, find how much time is requir...
 21.74PE: Integrated Concepts If you wish to take a picture of a bullet trave...
 21.75PE: Integrated Concepts A flashing lamp in a Christmas earring is based...
 21.76PE: Integrated Concepts A 160?F capacitor charged to 450 V is discharg...
 21.77PE: Unreasonable Results (a) Calculate the capacitance needed to get an...
 21.78PE: Construct Your Own a camera’s flash unit. Construct a problem in wh...
 21.79PE: Construct Your Own a rechargeable lithium cell that is to be used t...
Solutions for Chapter 21: College Physics 1st Edition
Full solutions for College Physics  1st Edition
ISBN: 9781938168000
Solutions for Chapter 21
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Solutions for Chapter 21
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Key Physics Terms and definitions covered in this textbook

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parallel

any symbol
average (indicated by a bar over a symbol—e.g., v¯ is average velocity)

°C
Celsius degree

°F
Fahrenheit degree