The fun and easy way to get up to speed on the basic concepts of physics For high school and undergraduate students alike, physics classes are recommended or required courses for a wide variety of majors, and continue to be a challenging and often confusing course. Physics I For Dummies tracks specifically to an introductory course and, keeping with the traditionally easy-to-follow Dummies style, teaches you the basic principles and formulas in a clear and concise manner, proving that you don't have to be Einstein to understand physics! Explains the basic principles in a simple, clear, and entertaining fashion New edition includes updated examples and explanations, as well as the newest discoveries in the field Contains the newest teaching techniques If just thinking about the laws of physics makes your head spin, this hands-on, friendly guide gets you out of the black hole and sheds light on this often-intimidating subject.

Table of Contents:
Introduction 1 About This Book 1 Conventions Used in This Book 2 What You’re Not to Read 2 Foolish Assumptions 2 How This Book Is Organized 3 Part 1: Putting Physics into Motion 3 Part 2: May the Forces of Physics Be with You 3 Part 3: Manifesting the Energy to Work 3 Part 4: Laying Down the Laws of Thermodynamics 3 Part 5: The Part of Tens 4 Icons Used in This Book 4 Where to Go from Here 4 Part 1: Putting Physics Into Motion 5 Chapter 1: Using Physics to Understand Your World 7 What Physics Is All About 8 Observing the world 8 Making predictions 9 Reaping the rewards 9 Observing Objects in Motion 10 Measuring speed, direction, velocity, and acceleration 10 Round and round: Rotational motion 11 Springs and pendulums: Simple harmonic motion 11 When Push Comes to Shove: Forces 12 Absorbing the energy around you 13 That’s heavy: Pressures in fluids 13 Feeling Hot but Not Bothered: Thermodynamics 14 Chapter 2: Reviewing Physics Measurement and Math Fundamentals 15 Measuring the World around You and Making Predictions 15 Using systems of measurement 16 From meters to inches and back again: Converting between units 17 Eliminating Some Zeros: Using Scientific Notation 19 Checking the Accuracy and Precision of Measurements 21 Knowing which digits are significant 21 Estimating accuracy 23 Arming Yourself with Basic Algebra 23 Tackling a Little Trig 24 Interpreting Equations as Real-World Ideas 25 Chapter 3: Exploring the Need for Speed 27 Going the Distance with Displacement 28 Understanding displacement and position 28 Examining axes 29 Speed Specifics: What Is Speed, Anyway? 32 Reading the speedometer: Instantaneous speed 32 Staying steady: Uniform speed 33 Shifting speeds: Non uniform motion 33 Busting out the stopwatch: Average speed 33 Speeding Up (Or Down): Acceleration 36 Defining acceleration 36 Determining the units of acceleration 36 Looking at positive and negative acceleration 37 Examining average and instantaneous acceleration 40 Taking off: Putting the acceleration formula into practice 41 Understanding uniform and non uniform acceleration 42 Relating Acceleration, Time, and Displacement 42 Not-so-distant relations: Deriving the formula 43 Calculating acceleration and distance 44 Linking Velocity, Acceleration, and Displacement 47 Finding acceleration 48 Solving for displacement 49 Finding final velocity 49 Chapter 4: Following Directions: Motion in Two Dimensions 51 Visualizing Vectors 52 Asking for directions: Vector basics 52 Looking at vector addition from start to finish 53 Going head-to-head with vector subtraction 54 Putting Vectors on the Grid 55 Adding vectors by adding coordinates 55 Changing the length: Multiplying a vector by a number 57 A Little Trig: Breaking Up Vectors into Components 57 Finding vector components 58 Reassembling a vector from its components 60 Featuring Displacement, Velocity, and Acceleration in 2-D 63 Displacement: Going the distance in two dimensions 64 Velocity: Speeding in a new direction 67 Acceleration: Getting a new angle on changes in velocity 68 Accelerating Downward: Motion under the Influence of Gravity 70 The golf-ball-off-the-cliff exercise 70 The how-far-can-you-kick-the-ball exercise 74 Part 2: May The Forces Of Physics Be With You 77 Chapter 5: When Push Comes to Shove: Force 79 Newton’s First Law: Resisting with Inertia 80 Resisting change: Inertia and mass 81 Measuring mass 82 Newton’s Second Law: Relating Force, Mass, and Acceleration 82 Relating the formula to the real world 83 Naming units of force 84 Vector addition: Gathering net forces 84 Newton’s Third Law: Looking at Equal and Opposite Forces 90 Seeing Newton’s third law in action 90 Pulling hard enough to overcome friction 91 Pulleys: Supporting double the force 92 Analyzing angles and force in Newton’s third law 94 Finding equilibrium 96 Chapter 6: Getting Down with Gravity, Inclined Planes, and Friction 99 Acceleration Due to Gravity: One of Life’s Little Constants 100 Finding a New Angle on Gravity with Inclined Planes 100 Finding the force of gravity along a ramp 101 Figuring the speed along a ramp 103 Getting Sticky with Friction 103 Calculating friction and the normal force 104 Conquering the coefficient of friction 105 On the move: Understanding static and kinetic friction 106 A not-so-slippery slope: Handling uphill and downhill friction 108 Let’s Get Fired Up! Sending Objects Airborne 113 Shooting an object straight up 113 Projectile motion: Firing an object at an angle 115 Chapter 7: Circling around Rotational Motion and Orbits 117 Centripetal Acceleration: Changing Direction to Move in a Circle 118 Keeping a constant speed with uniform circular motion 118 Finding the magnitude of the centripetal acceleration 120 Seeking the Center: Centripetal Force 121 Looking at the force you need 121 Seeing how the mass, velocity, and radius affect centripetal force 122 Negotiating flat curves and banked turns 123 Getting Angular with Displacement, Velocity, and Acceleration 126 Measuring angles in radians 126 Relating linear and angular motion 127 Letting Gravity Supply Centripetal Force 129 Using Newton’s law of universal gravitation 129 Deriving the force of gravity on the Earth’s surface 130 Using the law of gravitation to examine circular orbits 131 Looping the Loop: Vertical Circular Motion 135 Chapter 8: Go with the Flow: Looking at Pressure in Fluids 139 Mass Density: Getting Some Inside Information 140 Calculating density 140 Comparing densities with specific gravity 141 Applying Pressure 142 Looking at units of pressure 142 Connecting pressure to changes in depth 143 Hydraulic machines: Passing on pressure with Pascal’s principle 147 Buoyancy: Float Your Boat with Archimedes’s Principle 149 Fluid Dynamics: Going with Fluids in Motion 152 Characterizing the type of flow 152 Picturing flow with streamlines 154 Getting Up to Speed on Flow and Pressure 155 The equation of continuity: Relating pipe size and flow rates 155 Bernoulli’s equation: Relating speed and pressure 158 Pipes and pressure: Putting it all together 160 Part 3: Manifesting The Energy To Work 163 Chapter 9: Getting Some Work Out of Physics 165 Looking for Work 165 Working on measurement systems 166 Pushing your weight: Applying force in the direction of movement 166 Using a tow rope: Applying force at an angle 168 Negative work: Applying force opposite the direction of motion 170 Making a Move: Kinetic Energy 171 The work-energy theorem: Turning work into kinetic energy 171 Using the kinetic energy equation 173 Calculating changes in kinetic energy by using net force 174 Energy in the Bank: Potential Energy 176 To new heights: Gaining potential energy by working against gravity 177 Achieving your potential: Converting potential energy into kinetic energy 178 Choose Your Path: Conservative versus Non conservative Forces 179 Keeping the Energy Up: The Conservation of Mechanical Energy 180 Shifting between kinetic and potential energy 180 The mechanical-energy balance: Finding velocity and height 183 Powering Up: The Rate of Doing Work 184 Using common units of power 185 Doing alternate calculations of power 186 Chapter 10: Putting Objects in Motion: Momentum and Impulse 189 Looking at the Impact of Impulse 189 Gathering Momentum 191 The Impulse-Momentum Theorem: Relating Impulse and Momentum 192 Shooting pool: Finding force from impulse and momentum 193 Singing in the rain: An impulsive activity 195 When Objects Go Bonk: Conserving Momentum 196 Deriving the conservation formula 196 Finding velocity with the conservation of momentum 198 Finding firing velocity with the conservation of momentum 199 When Worlds (Or Cars) Collide: Elastic and Inelastic Collisions 201 Determining whether a collision is elastic 202 Colliding elastically along a line 203 Colliding elastically in two dimensions 205 Chapter 11: Winding Up with Angular Kinetics 209 Going from Linear to Rotational Motion 210 Understanding Tangential Motion 211 Finding tangential velocity 211 Finding tangential acceleration 213 Finding centripetal acceleration 214 Applying Vectors to Rotation 216 Calculating angular velocity 216 Figuring angular acceleration 217 Doing the Twist: Torque 219 Mapping out the torque equation 221 Understanding lever arms 223 Figuring out the torque generated 223 Recognizing that torque is a vector 225 Spinning at Constant Velocity: Rotational Equilibrium 225 Determining how much weight Hercules can lift 226 Hanging a flag: A rotational equilibrium problem 229 Ladder safety: Introducing friction into rotational equilibrium 231 Chapter 12: Round and Round with Rotational Dynamics 235 Rolling Up Newton’s Second Law into Angular Motion 235 Switching force to torque 236 Converting tangential acceleration to angular acceleration 237 Factoring in the moment of inertia 237 Moments of Inertia: Looking into Mass Distribution 238 DVD players and torque: A spinning-disk inertia example 240 Angular acceleration and torque: A pulley inertia example 242 Wrapping Your Head around Rotational Work and Kinetic Energy 244 Putting a new spin on work 245 Moving along with rotational kinetic energy 246 Let’s roll! Finding rotational kinetic energy on a ramp 247 Can’t Stop This: Angular Momentum 249 Conserving angular momentum 250 Satellite orbits: A conservation-of-angular-momentum example 250 Chapter 13: Springs ’n’ Things: Simple Harmonic Motion 253 Bouncing Back with Hooke’s Law 253 Stretching and compressing springs 254 Pushing or pulling back: The spring’s restoring force 254 Getting Around to Simple Harmonic Motion 256 Around equilibrium: Examining horizontal and vertical springs 256 Catching the wave: A sine of simple harmonic motion 258 Finding the angular frequency of a mass on a spring 264 Factoring Energy into Simple Harmonic Motion 267 Swinging with Pendulums 268 Part 4: Laying Down The Laws Of Thermodynamics 271 Chapter 14: Turning Up the Heat with Thermodynamics 273 Measuring Temperature 274 Fahrenheit and Celsius: Working in degrees 274 Zeroing in on the Kelvin scale 275 The Heat Is On: Thermal Expansion 276 Linear expansion: Getting longer 276 Volume expansion: Taking up more space 279 Heat: Going with the Flow (Of Thermal Energy) 281 Getting specific with temperature changes 282 Just a new phase: Adding heat without changing temperature 284 Chapter 15: Here, Take My Coat: How Heat Is Transferred 289 Convection: Letting the Heat Flow 289 Hot fluid rises: Putting fluid in motion with natural convection 290 Controlling the flow with forced convection 291 Too Hot to Handle: Getting in Touch with Conduction 292 Finding the conduction equation 293 Considering conductors and insulators 297 Radiation: Riding the (Electromagnetic) Wave 298 Mutual radiation: Giving and receiving heat 299 Blackbodies: Absorbing and reflecting radiation 300 Chapter 16: In the Best of All Possible Worlds: The Ideal Gas Law 305 Digging into Molecules and Moles with Avogadro’s Number 305 Relating Pressure, Volume, and Temperature with the Ideal Gas Law 307 Forging the ideal gas law 307 Working with standard temperature and pressure 309 A breathing problem: Checking your oxygen 310 Boyle’s and Charles’s laws: Alternative expressions of the ideal gas law 311 Tracking Ideal Gas Molecules with the Kinetic Energy Formula 313 Predicting air molecule speed 314 Calculating kinetic energy in an ideal gas 314 Chapter 17: Heat and Work: The Laws of Thermodynamics 317 Thermal Equilibrium: Getting Temperature with the Zeroth Law 318 Conserving Energy: The First Law of Thermodynamics 318 Calculating with conservation of energy 319 Staying constant: Isobaric, isochoric, isothermal, and adiabatic processes 322 Flowing from Hot to Cold: The Second Law of Thermodynamics 337 Heat engines: Putting heat to work 337 Limiting efficiency: Carnot says you can’t have it all 340 Going against the flow with heat pumps 343 Going Cold: The Third (And Absolute Last) Law of Thermodynamics 346 Part 5: The Part Of Tens 347 Chapter 18: Ten Physics Heroes 349 Galileo Galilei 349 Robert Hooke 350 Sir Isaac Newton 350 Benjamin Franklin 351 Charles-Augustin de Coulomb 352 Amedeo Avogadro 352 Nicolas Léonard Sadi Carnot 353 James Prescott Joule 353 William Thomson (Lord Kelvin) 353 Albert Einstein 354 Chapter 19: Ten Wild Physics Theories 355 You Can Measure a Smallest Distance 355 There May Be a Smallest Time 356 Heisenberg Says You Can’t Be Certain 356 Black Holes Don’t Let Light Out 357 Gravity Curves Space 357 Matter and Antimatter Destroy Each Other 358 Supernovas Are the Most Powerful Explosions 359 The Universe Starts with the Big Bang and Ends with the Gnab Gib 359 Microwave Ovens Are Hot Physics 360 Is the Universe Made to Measure? 361 Glossary 363 Index 367