Physics
Physics
1st Edition
Walker
ISBN: 9780133256925
Table of contents
Textbook solutions

All Solutions

Page 271: Practice Problems

Exercise 3
Step 1
1 of 3
**Given:**

The angular speed of the CD is $omega = 22 mathrm{~rad/s}$.

**Required:**

Finding the angular speed in revolutions per minute ($rpm$).

Step 2
2 of 3
**Calculation:**

In order to evaluate the angular speed in $rpm$, we should convert from radians per second to revolutions per minute.

$$begin{align*}
omega &= 22 mathrm{~rad/s} times dfrac{ 1 mathrm{~rev} }{ 2 pi mathrm{~rad} } times dfrac{ 60 mathrm{~s} }{ 1 mathrm{~min} } \
&= 210.085 mathrm{~rpm}
end{align*} $$

So, The angular speed in revolutions per minute ($rpm$) is $210.085 mathrm{~rpm}$.

Result
3 of 3
$$omega=210.085 mathrm{~rpm}$$
Exercise 4
Step 1
1 of 3
$textbf{Given: }$

The angular position change of the ceiling fan is $Delta theta = 45^{circ}$. The time interval that the fan takes to rotate is $Delta t = 0.75 mathrm{~s}$.

$textbf{Required: }$

Finding the angular speed of the fan in radians per second.

Step 2
2 of 3
$textbf{Calculation: }$

As we know the average angular velocity $omega_{avg}$ is given by the angular displacement divided by the time interval which the displacement occurs.

$$
begin{align*}
omega_{avg} &= dfrac{ Delta theta }{ Delta t } \
&= dfrac{ 45^{circ} }{ 0.75 mathrm{~s} } times dfrac{ 2 pi }{ 360^{circ} } \
&= dfrac{ pi }{3} mathrm{~rad/s}
end{align*}
$$

So, the average speed of the fan in radians per second is $dfrac{ pi }{3} mathrm{~rad/s}$.

Result
3 of 3
The average speed of the fan in radians per second is $dfrac{ pi }{3} mathrm{~rad/s}$.
Exercise 5
Step 1
1 of 3
$textbf{Given: }$

The angular speed of the airplane propeller is $omega = 260 mathrm{~rad/s}$. The time interval that the airplane propeller takes to rotate is $Delta t = 5 mathrm{~s}$.

$textbf{Required: }$

Finding the angular position change.

Step 2
2 of 3
$textbf{Calculation: }$

As we know the average angular velocity $omega_{avg}$ is given by the angular displacement divided by the time interval which the displacement occurs.

$$
begin{align*}
omega_{avg} &= dfrac{ Delta theta }{ Delta t } \
&= dfrac{ 45^{circ} }{ 0.75 mathrm{~s} } times dfrac{ 2 pi }{ 360^{circ} } \
&= dfrac{ pi }{3} mathrm{~rad/s}
end{align*}
$$

Rearrange and solve for the angular position change:

$$
begin{align*}
Delta theta &= omega_{avg} times Delta t \
&= 260 mathrm{~rad/s} times 5 mathrm{~s} \
&= 1300 mathrm{~rad} \
end{align*}
$$

In order to convert the angle in degrees instead of the radiansm we use the following relation:

$$
begin{align*}
Delta theta &= omega_{avg} times Delta t \
&= 260 mathrm{~rad/s} times 5 mathrm{~s} \
&= 1300 mathrm{~rad} \
&= 1300 mathrm{~rad} times dfrac{ 360^{circ} }{ 2 pi mathrm{~rad}} \
&= 74484.513^{circ} times left( 206 times 360^{circ} right) \
&= 324^{circ}
end{align*}
$$

So, the airplane propeller rotates with an angle equal to $1300 mathrm{~rad}$ in rad and $324^{circ}$ in degrees after $206$ completed cycles.

Result
3 of 3
The airplane propeller rotates with an angle equal to $1300 mathrm{~rad}$ in rad and $324^{circ}$ in degrees after $206$ completed cycles.
Exercise 6
Step 1
1 of 3
$textbf{Given: }$

The angular speed ofthe baseball is $omega = 38 mathrm{~rad/s}$. The angular displacment of the baseball is $Delta theta = 15^{circ}$.

$textbf{Required: }$

Finding the time interval that the baseball takes.

Step 2
2 of 3
$textbf{Calculation: }$

As we know the average angular velocity $omega_{avg}$ is given by the angular displacement divided by the time interval which the displacement occurs.

$$
begin{align*}
omega_{avg} &= dfrac{ Delta theta }{ Delta t }
end{align*}
$$

Rearrange and solve for the time interval that the baseball takes:

$$
begin{align*}
Delta t &= dfrac{ Delta theta }{ omega_{avg} } \
&= dfrac{15^{circ} }{ 38 mathrm{~rad/s} } times dfrac{ 2 pi }{ 360^{circ} } \
&= 6.89 times 10^{-3} mathrm{~s}
end{align*}
$$

So, the time interval that the baseball takes is $6.89 times 10^{-3} mathrm{~s}$.

Result
3 of 3
The time interval that the baseball takes is $6.89 times 10^{-3} mathrm{~s}$.
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Chapter 1: Introduction to Physics
Section 1.1: Physics and the Scientific Method
Section 1.2: Physics and Society
Section 1.3: Units and Dimensions
Section 1.4: Basic Math for Physics
Page 38: Assessment
Page 41: Standardized Test Prep
Chapter 2: Introduction to Motion
Section 2.1: Describing Motion
Section 2.2: Speed and Velocity
Section 2.3: Position-Time Graphs
Section 2.4: Equation of Motion
Page 66: Assessment
Page 71: Standardized Test Prep
Page 45: Practice Problems
Page 47: Practice Problems
Page 47: Lesson Check
Page 49: Practice Problems
Page 52: Practice Problems
Page 53: Lesson Check
Page 56: Practice Problems
Page 57: Lesson Check
Page 59: Practice Problems
Page 60: Practice Problems
Page 62: Practice Problems
Page 62: Lesson Check
Chapter 3: Acceleration and Acceleration Motion
Section 3.1: Acceleration
Section 3.2: Motion with Constant Acceleration
Section 3.3: Position-Time Graphs for Constant Acceleration
Section 3.4: Free Fall
Page 105: Assessment
Page 111: Standardized Test Prep
Chapter 4: Motion in Two Dimensions
Section 4.1: Vectors in Physics
Section 4.2: Adding and Subtracting Vectors
Section 4.3: Relative Motion
Section 4.4: Projectile Motion
Page 144: Assessment
Page 149: Standardized Test Prep
Chapter 5: Newton’s Laws of Motion
Section 5.1: Newton’s Laws of Motion
Section 5.2: Applying Newton’s Laws
Section 5.3: Friction
Page 180: Assessment
Page 187: Standardized Test Prep
Chapter 6: Work and Energy
Section 6.1: Work
Section 6.2: Work and Energy
Section 6.3: Conservation of Energy
Section 6.4: Power
Page 220: Assessment
Page 227: Standardized Test Prep
Page 191: Practice Problems
Page 193: Practice Problems
Page 196: Lesson Check
Page 196: Practice Problems
Page 199: Practice Problems
Page 201: Practice Problems
Page 203: Practice Problems
Page 204: Practice Problems
Page 205: Practice Problems
Page 206: Lesson Check
Page 209: Practice Problems
Page 211: Lesson Check
Page 213: Practice Problems
Page 214: Practice Problems
Page 215: Practice Problems
Page 216: Lesson Check
Chapter 7: Linear Momentum and Collisions
Section 7.1: Momentum
Section 7.2: Impulse
Section 7.3: Conservation of Momentum
Section 7.4: Collisions
Page 260: Assessment
Page 265: Standardized Test Prep
Chapter 8: Rotational Motion and Equilibrium
Section 8.1: Describing Angular Motion
Section 8.2: Rolling Motion and the Moment of Inertia
Section 8.3: Torque
Section 8.4: Static Equilibrium
Page 300: Assessment
Page 305: Standardized Test Prep
Page 269: Practice Problems
Page 271: Practice Problems
Page 272: Practice Problems
Page 275: Practice Problems
Page 275: Lesson Check
Page 277: Practice Problems
Page 280: Lesson Check
Page 284: Practice Problems
Page 286: Practice Problems
Page 287: Practice Problems
Page 289: Lesson Check
Page 294: Practice Problems
Page 295: Practice Problems
Page 296: Lesson Check
Chapter 9: Gravity and Circular Motion
Section 9.1: Newton’s Law of Universal Gravity
Section 9.2: Applications of Gravity
Section 9.3: Circular Motion
Section 9.4: Planetary Motion and Orbits
Page 336: Assessment
Page 341: Standardized Test Prep
Chapter 10: Temperature and Heat
Section 10.1: Temperature, Energy, and Heat
Section 10.2: Thermal Expansion and Energy Transfer
Section 10.3: Heat Capacity
Section 10.4: Phase Changes and Latent Heat
Page 378: Assessment
Page 383: Standardized Test Prep
Chapter 11: Thermodynamics
Section 11.1: The First Law of Thermodynamics
Section 11.2: Thermal Processes
Section 11.3: The Second and Third Laws of Thermodynamics
Page 410: Assessment
Page 413: Standardized Test Prep
Chapter 12: Gases, Liquids, and Solids
Section 12.1: Gases
Section 12.2: Fluids at Rest
Section 12.3: Fluids in Motion
Section 12.4: Solids
Page 446: Assessment
Page 451: Standardized Test Prep
Chapter 13: Oscillations and Waves
Section 13.1: Oscillations and Periodic Motion
Section 13.2: The Pendulum
Section 13.3: Waves and Wave Properties
Section 13.4: Interacting Waves
Page 486: Assessment
Page 491: Standardized Test Prep
Chapter 14: Sound
Section 14.1: Sound Waves and Beats
Section 14.2: Standing Sound Waves
Section 14.3: The Doppler Effect
Section 14.4: Human Perception of Sound
Page 523: Assessment
Page 527: Standardized Test Prep
Page 495: Practice Problems
Page 496: Practice Problems
Page 500: Practice Problems
Page 501: Lesson Check
Page 503: Practice Problems
Page 504: Practice Problems
Page 506: Practice Problems
Page 506: Lesson Check
Page 510: Practice Problems
Page 511: Practice Problems
Page 512: Lesson Check
Page 514: Practice Problems
Page 516: Practice Problems
Page 517: Practice Problems
Page 519: Lesson Check
Chapter 15: The Properties of Lights
Section 15.1: The Nature of Light
Section 15.2: Color and the Electromagnetic Spectrum
Section 15.3: Polarization and Scattering of Light
Page 557: Assessment
Page 563: Standardized Test Prep
Chapter 16: Reflection and Mirrors
Section 16.1: The Reflection of Light
Section 16.2: Plane Mirrors
Section 16.3: Curved Mirrors
Page 590: Assessment
Page 595: Standardized Test Prep
Chapter 17: Refraction and Lenses
Section 17.1: Refraction
Section 17.2: Applications of Refraction
Section 17.3: Lenses
Section 17.4: Applications of Lenses
Page 629: Assessment
Page 635: Standardized Test Prep
Chapter 18: Interference and Diffraction
Section 18.1: Interference
Section 18.2: Interference in Thin Films
Section 18.3: Diffraction
Section 18.4: Diffraction Gratings
Page 668: Assessment
Page 673: Standardized Test Prep
Chapter 19: Electric Charges and Forces
Section 19.1: Electric Charge
Section 19.2: Electric Force
Section 19.3: Combining Electric Forces
Page 698: Assessment
Page 703: Standardized Test Prep
Chapter 20: Electric Fields and Electric Energy
Section 20.1: The Electric Field
Section 20.2: Electric Potential Energy and Electric Potential
Section 20.3: Capacitance and Energy Storage
Page 738: Assessment
Page 743: Standardized Test Prep
Chapter 21: Electric Current and Electric Circuits
Section 21.1: Electric Current, Resistance, and Semiconductors
Section 21.2: Electric Circuits
Section 21.3: Power and Energy in Electric Circuits
Page 775: Assessment
Page 781: Standardized Test Prep
Chapter 22: Magnetism and Magnetic Fields
Section 22.1: Magnets and Magnetic Fields
Section 22.2: Magnetism and Electric Currents
Section 22.3: The Magnetic Force
Page 810: Assessment
Page 815: Standardized Test Prep
Chapter 23: Electromagnetic Induction
Section 23.1: Electricity from Magnetism
Section 23.2: Electric Generators and Motors
Section 23.3: AC Circuits and Transformers
Page 844: Assessment
Page 849: Standardized Test Prep
Chapter 24: Quantum Physics
Section 24.1: Quantized Energy and Photons
Section 24.2: Wave-Particle Duality
Section 24.3: The Heisenberg Uncertainty Principle
Page 876: Assessment
Page 881: Standardized Test Prep
Chapter 26: Nuclear Physics
Section 26.1: The Nucleus
Section 26.2: Radioactivity
Section 26.3: Applications of Nuclear Physics
Section 26.4: Fundamental Forces and Elementary Particles
Page 944: Assessment
Page 947: Standardized Test Prep