Question 1

Consider two copper wires with circular cross-sections and equal lengths. One wire has 3 times the diameter of the other. How do the resistances of these two wires compare?

Accepted Answer

A)   The thicker wire has  1/31 / 31/3  the resistance of the thinner wire.
B)   The thicker wire has 9 times the resistance of the thinner wire.
C)   The thicker wire has 3 times the resistance of the thinner wire.
D)   The thicker wire has  1/91 / 91/9  the resistance of the thinner wire.
E)   The thicker wire has  3\sqrt { 3 }3c-2.7,0,-7.17,-2.7,-13.5,-8c-5.8,-5.3,-9.5,-10,-9.5,-14c0,-2,0.3,-3.3,1,-4c1.3,-2.7,23.83,-20.7,67.5,-54c44.2,-33.3,65.8,-50.3,66.5,-51c1.3,-1.3,3,-2,5,-2c4.7,0,8.7,3.3,12,10s173,378,173,378c0.7,0,35.3,-71,104,-213c68.7,-142,137.5,-285,206.5,-429c69,-144,104.5,-217.7,106.5,-221l0 -0c5.3,-9.3,12,-14,20,-14H400000v40H845.2724s-225.272,467,-225.272,467s-235,486,-235,486c-2.7,4.7,-9,7,-19,7c-6,0,-10,-1,-12,-3s-194,-422,-194,-422s-65,47,-65,47zM834 80h400000v40h-400000z'/>​  times the resistance of the thinner wire. F) B) and D)
G) B) and C)

Question 2

A flashlight draws $0.133$ A from a $3.0$ - $V$ battery pack. In $2.0$ minutes (a) how much charge flows from the battery, (b) how much energy does the battery supply, and (c) how many electrons have passed any point in the circuit every second?

Accepted Answer

The answer of A flashlight draws $0.133$ A from a...

Question 3

If a quantity you calculated has units of  kg⋅m2 s⋅C2\frac { \mathrm { kg } \cdot \mathrm { m } ^ { 2 } } { \mathrm {~s} \cdot \mathrm { C } ^ { 2 } } s⋅C2kg⋅m2​  what is that quantity?

Accepted Answer

A)   capacitance
B)   resistivity
C)   potential
D)   resistance
E)   current F) A) and B)
G) A) and C)

Question 4

For the graph shown in the figure, what physical quantity does the slope of the graph represent for ohmic material?

Accepted Answer

A)   power
B)    1/1 /1/  (current) 
C)   resistivity
D)    1/1 /1/  (resistivity) 
E)   current F) C) and D)
G) B) and E)

Question 5

When a 14.0-A current flows through an 8.00-Ω device for 24.0 hours, how much does this cost if energy costs $0.0900 per kW · h?

Accepted Answer

A)    $0.24\$ 0.24$0.24 
B)    $2.16\$ 2.16$2.16 
C)    $3.39\$ 3.39$3.39 
D)    $1.04\$ 1.04$1.04E) B) and C)
F) None of the above

Question 6

The voltage drop across a metal bar is  5.0 V5.0 \mathrm {~V}5.0 V  while a current of  10.0 mA10.0 \mathrm {~mA}10.0 mA  flows through it. How much power does this bar dissipate?

Accepted Answer

A)    0.50 kW0.50 \mathrm {~kW}0.50 kW 
B)    500μW500 \mu \mathrm { W }500μW 
C)    2.5 kW2.5 \mathrm {~kW}2.5 kW 
D)    50 mW50 \mathrm {~mW}50 mWE) B) and C)
F) None of the above

Question 7

A charge of  12C12 \mathrm { C }12C  passes through an electroplating apparatus in  2.0 min2.0 \mathrm {~min}2.0 min . What is the average current in the apparatus?

Accepted Answer

A)    6.0 A6.0 \mathrm {~A}6.0 A 
B)    0.10 A0.10 \mathrm {~A}0.10 A 
C)    0.60 A0.60 \mathrm {~A}0.60 A 
D)    1.0 A1.0 \mathrm {~A}1.0 AE) None of the above
F) B) and C)

Question 8

If  3.0×10153.0 	imes 10^{15}3.0×1015  electrons flow through a section of a wire of diameter  2.0 mm2.0 \mathrm {~mm}2.0 mm  in  4.0 s4.0 \mathrm {~s}4.0 s , what is the current in the wire?  (e=1.60×10−19C) \left( e = 1.60 	imes 10 ^ { - 19 } \mathrm { C } ight) (e=1.60×10−19C)

Accepted Answer

A)    7.5×1014 A7.5 	imes 10 ^ { 14 } \mathrm {~A}7.5×1014 A 
B)    0.12 mA0.12 \mathrm {~mA}0.12 mA 
C)    0.24 mA0.24 \mathrm {~mA}0.24 mA 
D)    7.5×107 A7.5 	imes 10 ^ { 7 } \mathrm {~A}7.5×107 AE) All of the above
F) None of the above

Question 9

A  120−Ω120 - \Omega120−Ω  laboratory resistor is rated at  0.25 W0.25 \mathrm {~W}0.25 W . How much current can safely flow through the resistor?

Accepted Answer

A)    22 mA22 \mathrm {~mA}22 mA 
B)    30 A30 \mathrm {~A}30 A 
C)    46 mA46 \mathrm {~mA}46 mA 
D)    2.1 mA2.1 \mathrm {~mA}2.1 mAE) A) and B)
F) B) and C)

Question 10

What is the resistance of a cylindrical metal rod  1.0 cm1.0 \mathrm {~cm}1.0 cm  in diameter and  45 m45 \mathrm {~m}45 m  long, if the resistivity of the metal is  1.4×10−8Ω⋅m1.4 	imes 10 ^ { - 8 } \Omega \cdot \mathrm { m }1.4×10−8Ω⋅m  ?

Accepted Answer

A)    0.0080Ω0.0080 \Omega0.0080Ω 
B)    0.0063Ω0.0063 \Omega0.0063Ω 
C)    6.3Ω6.3 \Omega6.3Ω 
D)    0.80Ω0.80 \Omega0.80ΩE) B) and C)
F) C) and D)

Question 11

The resistance of a  100−cm100 - \mathrm { cm }100−cm  wire of cross sectional area  2×10−6 m22 	imes 10 ^ { - 6 } \mathrm {~m} ^ { 2 }2×10−6 m2  is  400Ω400 \Omega400Ω . What is the resistivity of the material from which this wire is made?

Accepted Answer

A)    0.80×10−5Ω⋅m0.80 	imes 10 ^ { - 5 } \Omega \cdot \mathrm { m }0.80×10−5Ω⋅m 
B)    0.80×10−6Ω⋅m0.80 	imes 10 ^ { - 6 } \Omega \cdot \mathrm { m }0.80×10−6Ω⋅m 
C)    8.0×10−4Ω⋅m8.0 	imes 10 ^ { - 4 } \Omega \cdot \mathrm { m }8.0×10−4Ω⋅m 
D)    8.0×10−6ΩV8.0 	imes 10 ^ { - 6 } \Omega \mathrm { V }8.0×10−6ΩV 
E)    0.80×10−4Ω⋅m0.80 	imes 10 ^ { - 4 } \Omega \cdot \mathrm { m }0.80×10−4Ω⋅mF) A) and D)
G) A) and B)

Question 12

A 1500-W heater is connected to a 120-V line for 2.0 hours. How much heat energy is produced?

Accepted Answer

A)    3.0 kJ3.0 \mathrm {~kJ}3.0 kJ 
B)    11MJ11 \mathrm { MJ }11MJ 
C)    1.5 kJ1.5 \mathrm {~kJ}1.5 kJ 
D)    0.18MJ0.18 \mathrm { MJ }0.18MJE) B) and C)
F) A) and D)

Question 13

What potential difference is required to cause  4.004.004.00  A to flow through a resistance of  330Ω330 \Omega330Ω  ?

Accepted Answer

A)    1320 V1320 \mathrm {~V}1320 V 
B)    334 V334 \mathrm {~V}334 V 
C)    12.1 V12.1 \mathrm {~V}12.1 V 
D)    82.5 V82.5 \mathrm {~V}82.5 VE) A) and B)
F) B) and C)

Question 14

A current of  5.05.05.0  A flows through an electrical device for 10 seconds. How many electrons flow through this device during this time?  (e=1.60×10−19C) \left( e = 1.60 	imes 10 ^ { - 19 } \mathrm { C } ight) (e=1.60×10−19C)

Accepted Answer

A)   20
B)    0.200.200.20 
C)    31×102031 	imes 10 ^ { 20 }31×1020 
D)    3.1×10203.1 	imes 10 ^ { 20 }3.1×1020 
E)    2.02.02.0F) B) and C)
G) None of the above

Question 15

A light bulb operating at a dc voltage of  120 V120 \mathrm {~V}120 V  has a power rating of  60 W60 \mathrm {~W}60 W . How much current is flowing through this bulb?

Accepted Answer

A)    1.5 A1.5 \mathrm {~A}1.5 A 
B)    2.5 A2.5 \mathrm {~A}2.5 A 
C)    1.0 A1.0 \mathrm {~A}1.0 A 
D)    0.50 A0.50 \mathrm {~A}0.50 A 
E)    2.0 A2.0 \mathrm {~A}2.0 AF) All of the above
G) B) and C)

Question 16

A  1.0−mm1.0 - \mathrm { mm }1.0−mm  diameter extension cord is made of metal having a resistivity of  1.68×10−8Ω⋅m1.68 	imes 10 ^ { - 8 } \Omega \cdot \mathrm { m }1.68×10−8Ω⋅m . When it carries a current of  15 A15 \mathrm {~A}15 A , what is the potential difference between two points in the cord that are  100 m100 \mathrm {~m}100 m  apart?

Accepted Answer

A)    41 V41 \mathrm {~V}41 V 
B)    32 V32 \mathrm {~V}32 V 
C)    23 V23 \mathrm {~V}23 V 
D)    12 V12 \mathrm {~V}12 VE) A) and B)
F) A) and C)

Exam 18: Electric Currents

The voltage drop across a metal bar is $5.0 \mathrm {~V}$ while a current of $10.0 \mathrm {~mA}$ flows through it. How much power does this bar dissipate?

Correct Answer
verified

If a quantity you calculated has units of $\frac { \mathrm { kg } \cdot \mathrm { m } ^ { 2 } } { \mathrm {~s} \cdot \mathrm { C } ^ { 2 } }$ what is that quantity?

Correct Answer
verified

What potential difference is required to cause $4.00$ A to flow through a resistance of $330 \Omega$ ?

Correct Answer
verified

When a 14.0-A current flows through an 8.00-Ω device for 24.0 hours, how much does this cost if energy costs $0.0900 per kW · h?

Correct Answer
verified

If $3.0 \times 10^{15}$ electrons flow through a section of a wire of diameter $2.0 \mathrm {~mm}$ in $4.0 \mathrm {~s}$ , what is the current in the wire? $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right)$

Correct Answer
verified

A current of $5.0$ A flows through an electrical device for 10 seconds. How many electrons flow through this device during this time? $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right)$

Correct Answer
verified

A $120 - \Omega$ laboratory resistor is rated at $0.25 \mathrm {~W}$ . How much current can safely flow through the resistor?

Correct Answer
verified

A flashlight draws $0.133$ A from a $3.0$ - $V$ battery pack. In $2.0$ minutes (a) how much charge flows from the battery, (b) how much energy does the battery supply, and (c) how many electrons have passed any point in the circuit every second?

Correct Answer
verified

A $1.0 - \mathrm { mm }$ diameter extension cord is made of metal having a resistivity of $1.68 \times 10 ^ { - 8 } \Omega \cdot \mathrm { m }$ . When it carries a current of $15 \mathrm {~A}$ , what is the potential difference between two points in the cord that are $100 \mathrm {~m}$ apart?

Correct Answer
verified

A light bulb operating at a dc voltage of $120 \mathrm {~V}$ has a power rating of $60 \mathrm {~W}$ . How much current is flowing through this bulb?

Correct Answer
verified

A charge of $12 \mathrm { C }$ passes through an electroplating apparatus in $2.0 \mathrm {~min}$ . What is the average current in the apparatus?

Correct Answer
verified

A 1500-W heater is connected to a 120-V line for 2.0 hours. How much heat energy is produced?

Correct Answer
verified

Consider two copper wires with circular cross-sections and equal lengths. One wire has 3 times the diameter of the other. How do the resistances of these two wires compare?

Correct Answer
verified

The resistance of a $100 - \mathrm { cm }$ wire of cross sectional area $2 \times 10 ^ { - 6 } \mathrm {~m} ^ { 2 }$ is $400 \Omega$ . What is the resistivity of the material from which this wire is made?

Correct Answer
verified

What is the resistance of a cylindrical metal rod $1.0 \mathrm {~cm}$ in diameter and $45 \mathrm {~m}$ long, if the resistivity of the metal is $1.4 \times 10 ^ { - 8 } \Omega \cdot \mathrm { m }$ ?

Correct Answer
verified

For the graph shown in the figure, what physical quantity does the slope of the graph represent for ohmic material?

Correct Answer
verified

Exam 18: Electric Currents

The voltage drop across a metal bar is 5.0 V5.0 \mathrm {~V}5.0 V while a current of 10.0 mA10.0 \mathrm {~mA}10.0 mA flows through it. How much power does this bar dissipate?

Correct AnswerverifiedShow Answer

If a quantity you calculated has units of kg⋅m2 s⋅C2\frac { \mathrm { kg } \cdot \mathrm { m } ^ { 2 } } { \mathrm {~s} \cdot \mathrm { C } ^ { 2 } } s⋅C2kg⋅m2​ what is that quantity?

Correct AnswerverifiedShow Answer

What potential difference is required to cause 4.004.004.00 A to flow through a resistance of 330Ω330 \Omega330Ω ?

Correct AnswerverifiedShow Answer

When a 14.0-A current flows through an 8.00-Ω device for 24.0 hours, how much does this cost if energy costs $0.0900 per kW · h?

Correct AnswerverifiedShow Answer

If 3.0×10153.0 \times 10^{15}3.0×1015 electrons flow through a section of a wire of diameter 2.0 mm2.0 \mathrm {~mm}2.0 mm in 4.0 s4.0 \mathrm {~s}4.0 s , what is the current in the wire? (e=1.60×10−19C) \left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right) (e=1.60×10−19C)

Correct AnswerverifiedShow Answer

A current of 5.05.05.0 A flows through an electrical device for 10 seconds. How many electrons flow through this device during this time? (e=1.60×10−19C) \left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right) (e=1.60×10−19C)

Correct AnswerverifiedShow Answer

A 120−Ω120 - \Omega120−Ω laboratory resistor is rated at 0.25 W0.25 \mathrm {~W}0.25 W . How much current can safely flow through the resistor?

Correct AnswerverifiedShow Answer

A flashlight draws 0.1330.1330.133 A from a 3.03.03.0 - VVV battery pack. In 2.02.02.0 minutes (a) how much charge flows from the battery, (b) how much energy does the battery supply, and (c) how many electrons have passed any point in the circuit every second?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A light bulb operating at a dc voltage of 120 V120 \mathrm {~V}120 V has a power rating of 60 W60 \mathrm {~W}60 W . How much current is flowing through this bulb?

Correct AnswerverifiedShow Answer

A charge of 12C12 \mathrm { C }12C passes through an electroplating apparatus in 2.0 min2.0 \mathrm {~min}2.0 min . What is the average current in the apparatus?

Correct AnswerverifiedShow Answer

A 1500-W heater is connected to a 120-V line for 2.0 hours. How much heat energy is produced?

Correct AnswerverifiedShow Answer

Consider two copper wires with circular cross-sections and equal lengths. One wire has 3 times the diameter of the other. How do the resistances of these two wires compare?

Correct AnswerverifiedShow Answer

The resistance of a 100−cm100 - \mathrm { cm }100−cm wire of cross sectional area 2×10−6 m22 \times 10 ^ { - 6 } \mathrm {~m} ^ { 2 }2×10−6 m2 is 400Ω400 \Omega400Ω . What is the resistivity of the material from which this wire is made?

Correct AnswerverifiedShow Answer

What is the resistance of a cylindrical metal rod 1.0 cm1.0 \mathrm {~cm}1.0 cm in diameter and 45 m45 \mathrm {~m}45 m long, if the resistivity of the metal is 1.4×10−8Ω⋅m1.4 \times 10 ^ { - 8 } \Omega \cdot \mathrm { m }1.4×10−8Ω⋅m ?

Correct AnswerverifiedShow Answer

For the graph shown in the figure, what physical quantity does the slope of the graph represent for ohmic material?

Correct AnswerverifiedShow Answer

The voltage drop across a metal bar is $5.0 \mathrm {~V}$ while a current of $10.0 \mathrm {~mA}$ flows through it. How much power does this bar dissipate?

Correct Answer
verified

If a quantity you calculated has units of $\frac { \mathrm { kg } \cdot \mathrm { m } ^ { 2 } } { \mathrm {~s} \cdot \mathrm { C } ^ { 2 } }$ what is that quantity?

Correct Answer
verified

What potential difference is required to cause $4.00$ A to flow through a resistance of $330 \Omega$ ?

Correct Answer
verified

Correct Answer
verified

If $3.0 \times 10^{15}$ electrons flow through a section of a wire of diameter $2.0 \mathrm {~mm}$ in $4.0 \mathrm {~s}$ , what is the current in the wire? $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right)$

Correct Answer
verified

A current of $5.0$ A flows through an electrical device for 10 seconds. How many electrons flow through this device during this time? $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } \right)$

Correct Answer
verified

A $120 - \Omega$ laboratory resistor is rated at $0.25 \mathrm {~W}$ . How much current can safely flow through the resistor?

Correct Answer
verified

A flashlight draws $0.133$ A from a $3.0$ - $V$ battery pack. In $2.0$ minutes (a) how much charge flows from the battery, (b) how much energy does the battery supply, and (c) how many electrons have passed any point in the circuit every second?

Correct Answer
verified

Correct Answer
verified

A light bulb operating at a dc voltage of $120 \mathrm {~V}$ has a power rating of $60 \mathrm {~W}$ . How much current is flowing through this bulb?

Correct Answer
verified

A charge of $12 \mathrm { C }$ passes through an electroplating apparatus in $2.0 \mathrm {~min}$ . What is the average current in the apparatus?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The resistance of a $100 - \mathrm { cm }$ wire of cross sectional area $2 \times 10 ^ { - 6 } \mathrm {~m} ^ { 2 }$ is $400 \Omega$ . What is the resistivity of the material from which this wire is made?

Correct Answer
verified

What is the resistance of a cylindrical metal rod $1.0 \mathrm {~cm}$ in diameter and $45 \mathrm {~m}$ long, if the resistivity of the metal is $1.4 \times 10 ^ { - 8 } \Omega \cdot \mathrm { m }$ ?

Correct Answer
verified

Correct Answer
verified