Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 21, Problem 23PCE
Two lightbulbs operate on the same potential difference. Bulb A has four times the power output of bulb B. (a) Which bulb has the greater current passing through it? Explain. (b) What is the ratio of the current in bulb A to the current in bulb B?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A heart defibrillator is used to enable the heart to start beating if it has stopped. This is done by passing a large current through the body at 25 V for a very
short time, usually about 3 millisecond. If 0.90 J of energy is transferred from the defibrillator to the body, what is the current that passed through the bod
y?
O 1,200 A
O 0.12 A
120 A
12 A
The figure shows conventional current passing through a resistor. The arrow shows the direction in which this conventional current is flowing. Which of the following statements are correct? (There could be more than one correct choice.)
a
The charges are moving slower at point b than at point a.
b
The electric potential is lower at point b than at point a.
c
The electric potential is higher at point b than at point a.
d
The current at point b is the same as the current at point a.
e
The electric potential at point b is the same as it is at point a.
A large spool in an electrician’s workshop has 75 m of insulation coated wire coiled around it. When the electrician connects a battery to the ends of the spooled wire, the resulting current is 2.4 A. Some weeks later, after cutting off various lengths of wire for use in repairs, the electrician finds that the spooled wire carries a 3.1-A current when the same battery is connected to it. What is the length of wire remaining on the spool?
Chapter 21 Solutions
Physics (5th Edition)
Ch. 21.1 - Enhance Your Understanding 1. The following...Ch. 21.2 - Enhance Your Understanding 2. If the voltage and...Ch. 21.3 - Enhance Your Understanding 3. In the following...Ch. 21.4 - The two circuits shown in Figure 21-17 have...Ch. 21.5 - Prob. 5EYUCh. 21.6 - Do two capacitors give a larger equivalent...Ch. 21.7 - Give a symbolic expression for the current that...Ch. 21 - Your body is composed of electric charges. Does it...Ch. 21 - Suppose you charge a comb by rubbing it through...Ch. 21 - An electron moving through a wire has an average...
Ch. 21 - Are car headlights connected in series or...Ch. 21 - Is it possible to connect a group of resistors of...Ch. 21 - What physical quantity do resistors connected in...Ch. 21 - What physical quantity do resistors connected in...Ch. 21 - Explain how electrical devices can begin operating...Ch. 21 - Explain the difference between resistivity and...Ch. 21 - Explain why birds can roost on high-voltage wires...Ch. 21 - Consider the circuit shown in Figure 21-36, in...Ch. 21 - A flashlight bulb carries a current of 0.38 A for...Ch. 21 - Predict/Calculate A car battery does 360 J of work...Ch. 21 - Highly sensitive ammeters can measure currents as...Ch. 21 - A television set connected to a 120-V outlet...Ch. 21 - BIO Pacemaker Batteries Pacemakers designed for...Ch. 21 - A conducting wire is quadrupled in length and...Ch. 21 - Figure 21-37 shows a plot of current versus...Ch. 21 - Predict/Explain Current-versus-voltage plots for...Ch. 21 - Prob. 9PCECh. 21 - When a potential difference of 12 V is applied to...Ch. 21 - Prob. 11PCECh. 21 - Prob. 12PCECh. 21 - Transcranial Direct-Current Stimulation In a tDCS...Ch. 21 - The four conducting cylinders shown in Figure...Ch. 21 - Predict/Calculate A bird lands on a bare copper...Ch. 21 - Prob. 16PCECh. 21 - Predict/Calculate BIO Current Through a Cell...Ch. 21 - Prob. 18PCECh. 21 - Prob. 19PCECh. 21 - BIO Resistance and Current in the Human Finger The...Ch. 21 - If a potential difference V is maintained between...Ch. 21 - Light A has four times the power rating of light B...Ch. 21 - Two lightbulbs operate on the same potential...Ch. 21 - Problems and Conceptual Exercises Section 21-3...Ch. 21 - A 65-V generator supplies 4.8 kW of power. How...Ch. 21 - A portable CD player operates with a current of 18...Ch. 21 - Find the power dissipated in a 22- electric heater...Ch. 21 - The current in a 120-V reading lamp is 2.6 A. If...Ch. 21 - Circuit A in a house has a voltage of 208 V and is...Ch. 21 - Predict/Calculate A 65-W lightbulb operates on a...Ch. 21 - Rating Car Batteries Car batteries are rated by...Ch. 21 - Predict/Explain A dozen identical lightbulbs are...Ch. 21 - A circuit consists of three resistors, R1 R2 R3,...Ch. 21 - Predict/Explain Two resistors are connected in...Ch. 21 - What is the minimum number of 88- resistors that...Ch. 21 - Find the equivalent resistance between points A...Ch. 21 - A 9.00-V battery is connected across the terminals...Ch. 21 - Holiday Lights In a string of holiday lights, 50...Ch. 21 - Your toaster has a power cord with a resistance of...Ch. 21 - Prob. 40PCECh. 21 - Predict/Calculate Three resistors, 11, 53 , and R,...Ch. 21 - A circuit consists of a battery connected to three...Ch. 21 - Predict/Calculate Three resistors, 22 , 67 , and...Ch. 21 - Prob. 44PCECh. 21 - The equivalent resistance between points A and B...Ch. 21 - Find the equivalent resistance between points A...Ch. 21 - How many 23-W lightbulbs can be connected in...Ch. 21 - The circuit in Figure 21-43 includes a battery...Ch. 21 - Predict/Calculate A 12-V battery is connected to...Ch. 21 - Predict/Calculate The terminals A and B in Figure...Ch. 21 - Predict/Calculate Suppose the battery in Figure...Ch. 21 - Predict/Calculate The current flowing through the...Ch. 21 - Predict/Calculate Four identical resistors are...Ch. 21 - Find the magnitude and direction (clockwise or...Ch. 21 - Predict/Calculate Suppose the polarity of the...Ch. 21 - Predict/Calculate It is given that point A in...Ch. 21 - Consider the circuit shown in Figure 21-47. Find...Ch. 21 - Suppose point A is grounded (V = 0) in Figure...Ch. 21 - Predict/Calculate (a) Find the current in each...Ch. 21 - Two batteries and three resistors are connected as...Ch. 21 - Two capacitors, C1 = C and C2 = 2C, are connected...Ch. 21 - Predict/Explain Two capacitors are connected in...Ch. 21 - Predict/Explain Two capacitors are connected in...Ch. 21 - A 252-F capacitor is connected in series with a...Ch. 21 - A 36-F capacitor is connected in parallel with an...Ch. 21 - Find the equivalent capacitance between points A...Ch. 21 - A 15-V battery is connected to three capacitors in...Ch. 21 - Three different circuits, each containing a switch...Ch. 21 - Terminals A and B in Figure 21-50 are connected to...Ch. 21 - Predict/Calculate You would like to add a second...Ch. 21 - Two capacitors, one 7.5 F and the other 15 F, are...Ch. 21 - The equivalent capacitance of the capacitors shown...Ch. 21 - With the switch in position A, the 11.2-F...Ch. 21 - The switch on an RC circuit is closed at t = 0....Ch. 21 - The capacitor in an RC circuit (R = 120 , C = 45...Ch. 21 - Three RC circuits have the emf, resistance, and...Ch. 21 - Consider an RC circuit with = 12.0 V, R = 195 ,...Ch. 21 - The resistor in an RC circuit has a resistance of...Ch. 21 - A flash unit for a camera has a capacitance of...Ch. 21 - Figure 21-54 shows a simplified circuit for a...Ch. 21 - Nerve Impulse Propagation The speed with which...Ch. 21 - Predict/Calculate Consider the RC circuit shown in...Ch. 21 - CE Consider the circuit shown in Figure 21-56, in...Ch. 21 - CE Predict/Explain (a) Referring to Problem 83 and...Ch. 21 - CE Consider the circuit shown in Figure 21-57, in...Ch. 21 - CE Predict/Explain (a) When the switch is closed...Ch. 21 - Suppose that points A and B in Figure 21-41 are...Ch. 21 - CE The circuit shown in Figure 21-58 shows a...Ch. 21 - CE The three circuits shown in Figure 21-59 have...Ch. 21 - Electrical Safety Codes For safety reasons,...Ch. 21 - A portable CD player uses a current of 7.5 mA at a...Ch. 21 - An electrical heating coil is immersed in 6.6 kg...Ch. 21 - Predict/Calculate Consider the circuit shown in...Ch. 21 - Prob. 94GPCh. 21 - BIO Pacemaker Pulses A pacemaker sends a pulse to...Ch. 21 - Three resistors (R,12R,2R) are connected to a...Ch. 21 - Predict/Calculate Suppose we connect a 12.0-V...Ch. 21 - National Electric Code In the United States, the...Ch. 21 - Solar Panel Power The current-versus-voltage plot...Ch. 21 - Predict/Calculate A 15.0-V battery is connected to...Ch. 21 - When two resistors, R1 and R2, are connected in...Ch. 21 - The circuit shown in Figure 21-62 is known as a...Ch. 21 - BIO Footwear Safety The American National...Ch. 21 - BIO Footwear Safety The American National...Ch. 21 - BIO Footwear Safety The American National...Ch. 21 - The standard specifies that footwear should be...Ch. 21 - Referring to Example 21-13 Suppose the three...Ch. 21 - Referring to Example 21-13 Suppose R1 = R2 = 225 ...Ch. 21 - Predict/Calculate Referring to Example 21-18...Ch. 21 - Predict/Calculate Referring to Example 21-18...
Additional Science Textbook Solutions
Find more solutions based on key concepts
Body, Heal Thyself The precision of mitotic cell division is essential for repairing damaged tissues like those...
Biology: Life on Earth with Physiology (11th Edition)
Plants use the process of photosynthesis to convert the energy in sunlight to chemical energy in the form of su...
Campbell Essential Biology with Physiology (5th Edition)
Where is transitional epithelium found and what is its importance at those sites?
Anatomy & Physiology (6th Edition)
Low-pressure centers are also referred to as ______, while high-pressure centers are called ______.
Applications and Investigations in Earth Science (9th Edition)
Describe an example of bioconversion. What metabolic processes can result in fuels?
Microbiology: An Introduction
Why are BSL-4 suits pressurized? Why not just wear tough regular suits?
Microbiology with Diseases by Body System (5th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- Integrated Concepts (a) What energy is dissipated by a lightning bolt having a 20,000-A current, a voltage of 1.00102 MV, and a length of 1.00 ms? (b) What mass of tree sap could be raised from 18.0°C to its boiling point and then evaporated by this energy, assuming sap has the same thermal characteristics as water?arrow_forwardAn electric eel generates electric currents through its highly specialized Hunters organ, in which thousands of disk-shaped cells called electrocytes are lined up in series, very much in the same way batteries are lined up inside a flashlight. When activated, each electrocyte can maintain a potential difference of about 150 mV at a current of 1.0 A for about 2.0 ms. Suppose a grown electric eel has 4.0 103 electrocytes and can deliver up to 3.00 102 shocks in rapid series over about 1.0 s. (a) What maximum electrical power can an electric eel generate? (b) Approximately how much energy does it release in one shock? (c) How high would a mass of 1.0 kg have to be lifted so that its gravitational potential energy equals the energy released in 3.00 102 such shocks?arrow_forwardA potential difference of 1.00 V is maintained across a 10.0- resistor for a period of 20.0 s. What total charge passes by a point in one of the wires connected to the resistor in this time interval? (a) 200 C (b) 20.0 C (c) 2.00 C (d) 0.005 00 C (e) 0.050 0 Carrow_forward
- In the circuit of Figure P18.22, the current I1 is 3.0 A and the values of and R are unknown. What are the currents I2 and I3? Figure P18.22arrow_forwardElectric fish generate current with biological cells called electroplaques, which are physiological emf devices. The electroplaques in the South American eel are arranged in 140 rows, each row stretching horizontally along the body and each containing 5000 electroplaques. Each electroplaque has an emf of 0.15 V and internal resistance of 0.25 . If the water surrounding the fish has resistance of 800 , how much current can the eel produce in water from near its head to near its tail?arrow_forwardTaking R = 1.00 k and = 250 V in Figure P21.49, determine the direction and magnitude of the current in the horizontal wire between a and e. Figure P21.49arrow_forward
- A large cyclotron directs a beam of He ++ nuclei onto a target with a beam current of 0.250 mA. (a) How many He++ nuclei per second is this? (b) How long does it take for 1.00 C to strike the target? (c) How long before 1.00 mol of He++ nuclei strike the target?arrow_forwardA particle accelerator produces a beam with a radius of 1.25 mm with a current of 2.00 mA. Each proton has a kinetic energy of 10.00 MeV. (a) What is the velocity of the protons? (b) What is the number (n) of protons per unit volume? (b) How many electrons pass a cross sectional area each second?arrow_forwardThe- pair of capacitors in Figure P28.63 are fully charged by a 12.0-V battery. The battery is disconnected, and the switch is then closed. Alter 1.00 ms has elapsed, (a) how much charge remains 011 the 3.00-F capacitor? (b) How much charge remains on the 2.00-F capacitor? (c) What is the current in the resistor at this time?arrow_forward
- A 20.00-V battery is used to supply current to a 10-k resistor. Assume the voltage drop across any wires used for connections is negligible, (a) What is the current through the resistor? (b) What is the power dissipated by the resistor? (c) What is the power input from the battery; assuming all the electrical power is dissipated by the resistor? (d) What happens to the energy dissipated by the resistor?arrow_forwardUnreasonable Results (a) What current is needed to transmit 1.00 102 MW of power at 10.0kV? (b) Find the resistance of 1.00 km of wire that would cause a 0.0100% power loss. (c) What is the diameter of a 1.00-km-long copper wire having this resistance? (d) What is unreasonable about these results? (e) Which assumptions are unreasonable, or which premises are inconsistent?arrow_forwardJumper cables are connected from a fresh battery in one car to charge a dead battery in another car. Figure P21.52 shows the circuit diagram for this situation. While the cables are connected, the ignition switch of the car with the dead battery is closed and the starter is activated to start the engine. Determine the current in (a) the starter and (b) the dead battery. (c) Is the dead battery being charged while the starter is operating? Figure P21.52 P21.52 Using Kirchhoffs rules and suppressing units, 12.0(0.01)I1(0.06)I3=0[1] 12.0+(1.00)I2(0.06)I3=0[2] andI1=I2+I3.[3] Substitute [3] into [1]: 12.0(0.01)(I2+I3)(0.06)I3=012.0(0.01)I2(0.07)I3=0[4] ANS. FIG. P21.52 Solving [4] and [2] simultaneously gives (a) I3 = 172 A = 172Adownward in the starter. (b) I2 = 1.70 A = 1.70Aupward in the dead battery. (c) No,thecurrentinthedeadbatteryisupwardinFigureP21.52,soitisnotbeingcharged.Thedeadbatteryisprovidingasmallamountofpowertooperatethestarter,soitisnotreallydead.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningCollege PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax College
- College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningPhysics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
College Physics
Physics
ISBN:9781285737027
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Physics for Scientists and Engineers, Technology ...
Physics
ISBN:9781305116399
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Circuits, Voltage, Resistance, Current - Physics 101 / AP Physics Review with Dianna Cowern; Author: Physics Girl;https://www.youtube.com/watch?v=q8X2gcPVwO0;License: Standard YouTube License, CC-BY