Question 1

In the diagram R1 > R2 > R3.Rank the three resistors according to the current in them, least to greatest.

Accepted Answer

A) 1, 2, 3 
B) 3, 2, 1 
C) 1, 3, 2 
D) 3, 1, 2 
E) All are the same 
A) 1, 2, 3 
B) 3, 2, 1 
C) 1, 3, 2 
D) 3, 1, 2 
E) All are the same

Question 2

A resistor with resistance R1 and a resistor with resistance R2 are connected in parallel to an ideal battery with emf   .The rate of thermal energy generation in the resistor with resistance R1 is:

Accepted Answer

A)    2/R1 
B)    2 R1/(R1 + R2)2 
C)    2 /(R1 + R2) 
D)    2/R2 
E)    
A)    2/R1 
B)    2 R1/(R1 + R2)2 
C)    2 /(R1 + R2) 
D)    2/R2 
E)

Question 3

An ideal battery has an emf of 12 V.If it is connected to a circuit and creates a current of 4.0 A, what is the power?

Accepted Answer

A) 0.3 W 
B) 3.0 W 
C) 36 W 
D) 48 W 
E) cannot tell without knowing the resistance of the circuit 
A) 0.3 W 
B) 3.0 W 
C) 36 W 
D) 48 W 
E) cannot tell without knowing the resistance of the circuit

Question 4

For any circuit the number of independent equations containing emf's, resistances, and currents equals:

Accepted Answer

A) the number of junctions 
B) the number of junctions minus 1 
C) the number of branches 
D) the number of branches minus 1 
E) the number of closed loops 
A) the number of junctions 
B) the number of junctions minus 1 
C) the number of branches 
D) the number of branches minus 1 
E) the number of closed loops

Question 5

The emf of a battery is equal to its terminal potential difference:

Accepted Answer

A) under all conditions 
B) only when the battery is being charged 
C) only when a large current is in the battery 
D) only when there is no current in the battery 
E) under no conditions 
A) under all conditions 
B) only when the battery is being charged 
C) only when a large current is in the battery 
D) only when there is no current in the battery 
E) under no conditions

Question 6

Nine identical wires, each of diameter d and length L, are connected in series.The combination has the same resistance as a single similar wire of length L but whose diameter is:

Accepted Answer

A) 9d 
B) 3d 
C) d/3 
D) d/9 
E) d/81 
A) 9d 
B) 3d 
C) d/3 
D) d/9 
E) d/81

Question 7

"The sum of the currents into a junction equals the sum of the currents out of the junction" is a consequence of:

Accepted Answer

A) Newton's third law 
B) Ohm's law 
C) Newton's second law 
D) conservation of energy 
E) conservation of charge 
A) Newton's third law 
B) Ohm's law 
C) Newton's second law 
D) conservation of energy 
E) conservation of charge

Question 8

When switch S is open, the ammeter in the circuit shown reads 2.0 A.When S is closed, the ammeter reading:

Accepted Answer

A) increases slightly 
B) remains the same 
C) decreases slightly 
D) doubles 
E) halves 
A) increases slightly 
B) remains the same 
C) decreases slightly 
D) doubles 
E) halves

Question 9

Four circuits have the form shown in the diagram.The capacitor is initially uncharged and the switch S is open.    Rank the circuits according to the current just after switch S is closed least to greatest.

Accepted Answer

A) 1, 2, 3, 4 
B) 4, 3, 2, 1 
C) 4, 2, 3, 1 
D) 4, 2, 1, 3 
E) 3, 1, 2, 4 
A) 1, 2, 3, 4 
B) 4, 3, 2, 1 
C) 4, 2, 3, 1 
D) 4, 2, 1, 3 
E) 3, 1, 2, 4

Question 10

In the diagrams, all light bulbs are identical and all emf devices are identical.In which circuit (I, II, III, IV, V)will the bulbs be dimmest?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
E) V 
A) I 
B) II 
C) III 
D) IV 
E) V

Question 11

In the diagram, the current in the 3-$\Omega$ resistor is 4 A.The potential difference between points 1 and 2 is:

Accepted Answer

A) 0.75 V 
B) 0.8 V 
C) 1.25 V 
D) 12 V 
E) 20 V 
A) 0.75 V 
B) 0.8 V 
C) 1.25 V 
D) 12 V 
E) 20 V

Question 12

An initially uncharged capacitor C is connected in series with resistor R.This combination is then connected to a battery of emf V0.Sufficient time elapses so that a steady state is reached.Which of the following statements is NOT true?

Accepted Answer

A) The time constant is independent of V0 
B) The final charge on C is independent of R 
C) The total energy dissipated by R is independent of R 
D) The total energy dissipated by R is independent of V0 
E) The initial current (just after the battery was connected)is independent of C 
A) The time constant is independent of V0 
B) The final charge on C is independent of R 
C) The total energy dissipated by R is independent of R 
D) The total energy dissipated by R is independent of V0 
E) The initial current (just after the battery was connected)is independent of C

Question 13

The current in the 5.0-$\Omega$resistor in the circuit shown is:

Accepted Answer

A) 0.42 A 
B) 0.67 A 
C) 1.5 A 
D) 2.4 A 
E) 3.0 A 
A) 0.42 A 
B) 0.67 A 
C) 1.5 A 
D) 2.4 A 
E) 3.0 A

Question 14

Two identical batteries, each with an emf of 18 V and an internal resistance of 1 $\Omega$, are wired in parallel by connecting their positive terminals together and connecting their negative terminals together.The combination is then wired across a 4-$\Omega$ resistor.The potential difference across the 4-$\Omega$ resistor is:

Accepted Answer

A) 4.0 V 
B) 8.0 V 
C) 14 V 
D) 16 V 
E) 29 V 
A) 4.0 V 
B) 8.0 V 
C) 14 V 
D) 16 V 
E) 29 V

Question 15

A battery of emf 24 V is connected to a 6.0- $\Omega$  resistor.As a result, current of 3.0 A exists in the resistor.The rate at which energy is being dissipated in the battery is:

Accepted Answer

A) 3.0 W 
B) 6.0 W 
C) 18 W 
D) 54 W 
E) 72 W 
A) 3.0 W 
B) 6.0 W 
C) 18 W 
D) 54 W 
E) 72 W

Question 16

A portion of a circuit is shown, with the values of the currents given for some branches.What is the direction and value of the current i?

Accepted Answer

A) " $\downarrow$ , 6A" 
B) " $\uparrow$ , 6A" 
C) " $\downarrow$ , 4A" 
D) " $\uparrow$ , 4A" 
E) " $\downarrow$ , 2A" 
A) " $\downarrow$ , 6A" 
B) " $\uparrow$ , 6A" 
C) " $\downarrow$ , 4A" 
D) " $\uparrow$ , 4A" 
E) " $\downarrow$ , 2A"

Question 17

A battery is connected across a series combination of two identical resistors.If the potential difference across the terminals is V and the current in the battery is i, then:

Accepted Answer

A) the potential difference across each resistor is V and the current in each resistor is i 
B) the potential difference across each resistor is V/2 and the current in each resistor is i/2 
C) the potential difference across each resistor is V and the current in each resistor is i/2 
D) the potential difference across each resistor is V/2 and the current in each resistor is i 
E) none of the above are true 
A) the potential difference across each resistor is V and the current in each resistor is i 
B) the potential difference across each resistor is V/2 and the current in each resistor is i/2 
C) the potential difference across each resistor is V and the current in each resistor is i/2 
D) the potential difference across each resistor is V/2 and the current in each resistor is i 
E) none of the above are true

Question 18

Two identical batteries, each with an emf of 18 V and an internal resistance of 1 $\Omega$, are wired in parallel by connecting their positive terminals together and connecting their negative terminals together.The combination is then wired across a 4-$\Omega$ resistor.The current in the 4-$\Omega$ resistor is:

Accepted Answer

A) 2.0 A 
B) 3.6 A 
C) 4.0 A 
D) 7.2 A 
E) 9.0 A 
A) 2.0 A 
B) 3.6 A 
C) 4.0 A 
D) 7.2 A 
E) 9.0 A

Question 19

Two wires are made of the same material and have the same length but different radii.They are joined end-to-end and a potential difference is maintained across the combination.Of the following the quantity that is the same for both wires is:

Accepted Answer

A) potential difference 
B) current 
C) current density 
D) electric field 
E) conduction electron drift speed 
A) potential difference 
B) current 
C) current density 
D) electric field 
E) conduction electron drift speed

Question 20

A certain ammeter has an internal resistance of 1 $\Omega$ and a range from 0 to 50 mA.To make its range from 0 to 5 A, use:

Accepted Answer

A) a series resistance of 99 $\Omega$ 
B) an extremely large (say 106 $\Omega$series resistance 
C) a resistance of 99 $\Omega$in parallel 
D) a resistance of 1/99 $\Omega$ in parallel 
E) a resistance of 1/1000 $\Omega$ in parallel 
A) a series resistance of 99 $\Omega$ 
B) an extremely large (say 106 $\Omega$series resistance 
C) a resistance of 99 $\Omega$in parallel 
D) a resistance of 1/99 $\Omega$ in parallel 
E) a resistance of 1/1000 $\Omega$ in parallel

Exam 27: Circuits

In the diagram R1 > R2 > R3.Rank the three resistors according to the current in them, least to greatest.

A resistor with resistance R1 and a resistor with resistance R2 are connected in parallel to an ideal battery with emf .The rate of thermal energy generation in the resistor with resistance R1 is:

An ideal battery has an emf of 12 V.If it is connected to a circuit and creates a current of 4.0 A, what is the power?

For any circuit the number of independent equations containing emf's, resistances, and currents equals:

The emf of a battery is equal to its terminal potential difference:

Nine identical wires, each of diameter d and length L, are connected in series.The combination has the same resistance as a single similar wire of length L but whose diameter is:

"The sum of the currents into a junction equals the sum of the currents out of the junction" is a consequence of:

When switch S is open, the ammeter in the circuit shown reads 2.0 A.When S is closed, the ammeter reading:

Four circuits have the form shown in the diagram.The capacitor is initially uncharged and the switch S is open. Rank the circuits according to the current just after switch S is closed least to greatest.

In the diagrams, all light bulbs are identical and all emf devices are identical.In which circuit (I, II, III, IV, V)will the bulbs be dimmest?

In the diagram, the current in the 3- Ω\OmegaΩ resistor is 4 A.The potential difference between points 1 and 2 is:

An initially uncharged capacitor C is connected in series with resistor R.This combination is then connected to a battery of emf V0.Sufficient time elapses so that a steady state is reached.Which of the following statements is NOT true?

The current in the 5.0- Ω\OmegaΩ resistor in the circuit shown is:

A battery of emf 24 V is connected to a 6.0- Ω\OmegaΩ resistor.As a result, current of 3.0 A exists in the resistor.The rate at which energy is being dissipated in the battery is:

A portion of a circuit is shown, with the values of the currents given for some branches.What is the direction and value of the current i?

A battery is connected across a series combination of two identical resistors.If the potential difference across the terminals is V and the current in the battery is i, then:

Two wires are made of the same material and have the same length but different radii.They are joined end-to-end and a potential difference is maintained across the combination.Of the following the quantity that is the same for both wires is:

A certain ammeter has an internal resistance of 1 Ω\OmegaΩ and a range from 0 to 50 mA.To make its range from 0 to 5 A, use:

Measurement

Motion Along a Straight Line

Vectors

Motion in Two and Three Dimensions

Force and Motion

Force and Motion

Kinetic Energy and Work

Potential Energy and Conservation of Energy

Center of Mass and Linear Momentum

Rotation

Rolling, Torque, and Angular Momentum

Equilibrium and Elasticity

Gravitation

Fluids

Oscillations

Waves

Waves

Temperature, Heat, and the First Law of Thermodynamics

The Kinetic Theory of Gases

Entropy and the Second Law of Thermodynamics

Coulombs Law

Electric Fields

Gauss Law

Electric Potential

Capacitance

Current and Resistance

Magnetic Fields

Magnetic Fields Due to Currents

Induction and Inductance

Electromagnetic Oscillations and Alternating Current

Maxwells Equations; Magnetism of Matter

Electromagnetic Waves

Images

Interference 1

Diffraction

Relativity

Photons and Matter Waves

More About Matter Waves

All About Atoms

Conduction of Electricity in Solids

Energy From the Nucleus

Quarks, Leptons, and the Big Bang

Filters

In the diagram R₁ > R₂ > R₃.Rank the three resistors according to the current in them, least to greatest.

A resistor with resistance R₁ and a resistor with resistance R₂ are connected in parallel to an ideal battery with emf .The rate of thermal energy generation in the resistor with resistance R₁ is:

In the diagram, the current in the 3- $\Omega$ resistor is 4 A.The potential difference between points 1 and 2 is: $In the diagram, the current in the 3- \Omega resistor is 4 A.The potential difference between points 1 and 2 is:$

An initially uncharged capacitor C is connected in series with resistor R.This combination is then connected to a battery of emf V₀.Sufficient time elapses so that a steady state is reached.Which of the following statements is NOT true?

The current in the 5.0- $\Omega$ resistor in the circuit shown is: $The current in the 5.0- \Omega resistor in the circuit shown is:$

A battery of emf 24 V is connected to a 6.0- $\Omega$ resistor.As a result, current of 3.0 A exists in the resistor.The rate at which energy is being dissipated in the battery is:

A certain ammeter has an internal resistance of 1 $\Omega$ and a range from 0 to 50 mA.To make its range from 0 to 5 A, use: