Question 1

If R1 = 10 Ω,R2 = 15 Ω,R3 = 20 Ω,and I = 0.50 A,at what rate is heat being generated in these resistors?

Accepted Answer

A) 29 W 
B) 16 W 
C) 22 W 
D) 11 W 
E) 1.1 W 
A) 29 W 
B) 16 W 
C) 22 W 
D) 11 W 
E) 1.1 W

Question 2

What is the magnitude of the potential difference across the 20-Ω resistor?

Accepted Answer

A) 3.2 V 
B) 7.8 V 
C) 11 V 
D) 5.0 V 
E) 8.6 V 
A) 3.2 V 
B) 7.8 V 
C) 11 V 
D) 5.0 V 
E) 8.6 V

Question 3

The circuit below contains three 100-W light bulbs and a capacitor.The emf ε = 110V.At the instant the switch S is closed,which light bulb is brightest?

Accepted Answer

A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright. 
A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright.

Question 4

What is the equivalent resistance between points a and b when R = 13 Ω?

Accepted Answer

A) 29 Ω 
B) 23 Ω 
C) 26 Ω 
D) 20 Ω 
E) 4.6 Ω 
A) 29 Ω 
B) 23 Ω 
C) 26 Ω 
D) 20 Ω 
E) 4.6 Ω

Question 5

What is the equivalent resistance between points a and b?

Accepted Answer

A) 14 Ω 
B) 8.0 Ω 
C) 6.0 Ω 
D) 25 Ω 
E) 40 Ω 
A) 14 Ω 
B) 8.0 Ω 
C) 6.0 Ω 
D) 25 Ω 
E) 40 Ω

Question 6

How long will it take a charged 80-μF capacitor to lose 20% of its initial energy when it is allowed to discharge through a 45-Ω resistor?

Accepted Answer

A) 0.92 ms 
B) 0.64 ms 
C) 0.40 ms 
D) 0.19 ms 
E) 0.80 ms 
A) 0.92 ms 
B) 0.64 ms 
C) 0.40 ms 
D) 0.19 ms 
E) 0.80 ms

Question 7

The circuit below contains three 100-watt light bulbs and a capacitor.The emf ε = 110V.The capacitor is fully charged.Which light bulb(s)is(are)dimmest?

Accepted Answer

A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright (or dim). 
A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright (or dim).

Question 8

At t = 0 the switch S is closed with the capacitor uncharged.If C = 30 μF,ε = 30 V,and R = 5.0 kΩ,at what rate is energy being stored in the capacitor when I = 2.0 mA?

Accepted Answer

A) 32 mW 
B) 40 mW 
C) 44 mW 
D) 36 mW 
E) 80 mW 
A) 32 mW 
B) 40 mW 
C) 44 mW 
D) 36 mW 
E) 80 mW

Question 9

Determine the magnitude and sense (direction)of the current in the 10-Ω resistor when I = 1.8 A.

Accepted Answer

A) 1.6 A right to left 
B) 1.6 A left to right 
C) 1.2 A right to left 
D) 1.2 A left to right 
E) 1.8 A left to right 
A) 1.6 A right to left 
B) 1.6 A left to right 
C) 1.2 A right to left 
D) 1.2 A left to right 
E) 1.8 A left to right

Question 10

At what rate is power supplied by the 10-V emf shown below?

Accepted Answer

A) −10 W 
B) +10 W 
C) zero 
D) +20 W 
E) −20 W 
A) −10 W 
B) +10 W 
C) zero 
D) +20 W 
E) −20 W

Question 11

If 480 C pass through a 4.0-Ω resistor in 10 min,what is the potential difference across the resistor?

Accepted Answer

A) 3.6 V 
B) 2.8 V 
C) 2.4 V 
D) 3.2 V 
E) 5.0 V 
A) 3.6 V 
B) 2.8 V 
C) 2.4 V 
D) 3.2 V 
E) 5.0 V

Question 12

If Q = 350 μC and I = 4.0 mA in the circuit segment shown below,determine the potential difference,VA − VB.

Accepted Answer

A) −30 V 
B) +80 V 
C) +40 V 
D) −40 V 
E) +10 V 
A) −30 V 
B) +80 V 
C) +40 V 
D) −40 V 
E) +10 V

Question 13

At t = 0 the switch S is closed with the capacitor uncharged.If C = 30 μF,ε = 50 V,and R = 10 kΩ,what is the potential difference across the capacitor when I = 2.0 mA?

Accepted Answer

A) 20 V 
B) 15 V 
C) 25 V 
D) 30 V 
E) 45 V 
A) 20 V 
B) 15 V 
C) 25 V 
D) 30 V 
E) 45 V

Question 14

At what rate is thermal energy generated in the 30-Ω resistor?

Accepted Answer

A) 20 W 
B) 27 W 
C) 60 W 
D) 13 W 
E) 30 W 
A) 20 W 
B) 27 W 
C) 60 W 
D) 13 W 
E) 30 W

Question 15

Which of the identical light bulb(s)is(are)brightest when the capacitor has half its maximum charge?

Accepted Answer

A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright. 
A) A 
B) B 
C) C 
D) A and B 
E) All three are equally bright.

Question 16

How many time constants must elapse if an initially charged capacitor is to discharge 55% of its stored energy through a resistor?

Accepted Answer

A) 0.60 
B) 0.46 
C) 0.52 
D) 0.40 
E) 1.1 
A) 0.60 
B) 0.46 
C) 0.52 
D) 0.40 
E) 1.1

Question 17

What is the current in the 10-Ω resistor ?

Accepted Answer

A) 0.60 A 
B) 3.0 A 
C) 1.2 A 
D) 2.4 A 
E) 0.30 A 
A) 0.60 A 
B) 3.0 A 
C) 1.2 A 
D) 2.4 A 
E) 0.30 A

Question 18

How much heat is produced in the 10-Ω resistor in 5.0 s when ε = 18 V?

Accepted Answer

A) 72 J 
B) 32 J 
C) 50 J 
D) 18 J 
E) 90 J 
A) 72 J 
B) 32 J 
C) 50 J 
D) 18 J 
E) 90 J

Question 19

If R = 2.0 kΩ,C = 4.0 mF,ε = 8.0 V,Q = 20 mC,and I = 3.0 mA,what is the potential difference Vb − Va?

Accepted Answer

A) +7.0 V 
B) +19 V 
C) +9.0 V 
D) −3.0 V 
E) −14 V 
A) +7.0 V 
B) +19 V 
C) +9.0 V 
D) −3.0 V 
E) −14 V

Question 20

The circuit below contains three 100-watt light bulbs.The emf ε = 110 V.Which light bulb(s)is(are)the brightest?

Accepted Answer

A) A 
B) B 
C) C 
D) B and C 
E) All three are equally bright. 
A) A 
B) B 
C) C 
D) B and C 
E) All three are equally bright.

Exam 28: Direct-Current Circuits

If R1 = 10 Ω,R2 = 15 Ω,R3 = 20 Ω,and I = 0.50 A,at what rate is heat being generated in these resistors?

What is the magnitude of the potential difference across the 20-Ω resistor?

The circuit below contains three 100-W light bulbs and a capacitor.The emf ε = 110V.At the instant the switch S is closed,which light bulb is brightest?

What is the equivalent resistance between points a and b when R = 13 Ω?

What is the equivalent resistance between points a and b?

How long will it take a charged 80-μF capacitor to lose 20% of its initial energy when it is allowed to discharge through a 45-Ω resistor?

The circuit below contains three 100-watt light bulbs and a capacitor.The emf ε = 110V.The capacitor is fully charged.Which light bulb(s)is(are)dimmest?

At t = 0 the switch S is closed with the capacitor uncharged.If C = 30 μF,ε = 30 V,and R = 5.0 kΩ,at what rate is energy being stored in the capacitor when I = 2.0 mA?

Determine the magnitude and sense (direction)of the current in the 10-Ω resistor when I = 1.8 A.

At what rate is power supplied by the 10-V emf shown below?

If 480 C pass through a 4.0-Ω resistor in 10 min,what is the potential difference across the resistor?

If Q = 350 μC and I = 4.0 mA in the circuit segment shown below,determine the potential difference,VA − VB.

At t = 0 the switch S is closed with the capacitor uncharged.If C = 30 μF,ε = 50 V,and R = 10 kΩ,what is the potential difference across the capacitor when I = 2.0 mA?

At what rate is thermal energy generated in the 30-Ω resistor?

Which of the identical light bulb(s)is(are)brightest when the capacitor has half its maximum charge?

How many time constants must elapse if an initially charged capacitor is to discharge 55% of its stored energy through a resistor?

What is the current in the 10-Ω resistor ?

How much heat is produced in the 10-Ω resistor in 5.0 s when ε = 18 V?

If R = 2.0 kΩ,C = 4.0 mF,ε = 8.0 V,Q = 20 mC,and I = 3.0 mA,what is the potential difference Vb − Va?

The circuit below contains three 100-watt light bulbs.The emf ε = 110 V.Which light bulb(s)is(are)the brightest?

Physics and Measurement

Motion in One Dimension

Vectors

Motion in Two Dimensions

The Laws of Motion

Circular Motion and Other Applications of Newtons Laws

Energy of a System

Conservation of Energy

Linear Momentum and Collisions

Rotation of a Rigid Object About a Fixed Axis

Angular Momentum

Static Equilibrium and Elasticity

Universal Gravitation

Fluid Mechanics

Oscillatory Motion

Wave Motion

Sound Waves

Superposition and Standing Waves

Temperature

The First Law of Thermodynamics

The Kinetic Theory of Gases

Heat Engines, entropy, and the Second Law of Thermodynamics

Electric Fields

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current and Resistance

Magnetic Fields

Sources of the Magnetic Field

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarization

Relativity

Introduction to Quantum Physics

Quantum Mechanics

Atomic Physics

Molecules and Solids

Nuclear Structure

Applications of Nuclear Physics

Particle Physics and Cosmology

Filters

If R₁ = 10 Ω,R₂ = 15 Ω,R₃ = 20 Ω,and I = 0.50 A,at what rate is heat being generated in these resistors?

If Q = 350 μC and I = 4.0 mA in the circuit segment shown below,determine the potential difference,V_A − V_B.

If R = 2.0 kΩ,C = 4.0 mF,ε = 8.0 V,Q = 20 mC,and I = 3.0 mA,what is the potential difference V_b − V_a?