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States of Matter Kinetic Molecular Theory Four States of Matter Thermal Expansion

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States of Matter Kinetic Molecular Theory Four States of Matter Thermal Expansion

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  1. MATTER States of Matter Kinetic Molecular Theory Four States of Matter Thermal Expansion
  2. Kinetic Molecular Theory KMT Tiny, constantly moving particles make up all matter. The kinetic energy (motion) of these particles increases as temperature increases.
  3. Four States of Matter Solids low KE - particles vibrate but can’t move around definite shape & volume crystalline - repeating geometric pattern amorphous - no pattern (e.g. glass, wax)
  4. Four States of Matter Liquids higher KE - particles can move around but are still close together indefinite shape definite volume
  5. Four States of Matter Gases high KE - particles can separate and move throughout container indefinite shape & volume
  6. Four States of Matter Plasma very high KE - particles collide with enough energy to break into charged particles (+/-) gas-like, indefiniteshape & volume stars, fluorescentlight bulbs, TV tubes
  7. Thermal Expansion Most matter expands when heated & contracts when cooled.  Temp causes  KE. Particles collide with more force & spread out. Thermal Expansion Joint in a Bridge
  8. Phase Changes Solid to Liquid Melting Liquid to Solid Freezing Melting point = Freezing point
  9. Phase Changes Vaporization (boiling) liquid to gas at the boiling point Evaporation liquid to gas below the boiling point Condensation gas to liquid
  10. Phase Changes Sublimation solid to gas EX: dry ice, freeze drying, iodine
  11. Phase Changes
  12. MIXTURE PURE SUBSTANCE yes no yes no Is the composition uniform? Can it be decomposed by chemical means? Matter Flowchart MATTER yes no Can it be separated by physical means? Homogeneous Mixture (solution) Heterogeneous Mixture Compound Element
  13. Pure Substances Element matter composed of identical atoms EX: copper
  14. Pure Substances Compound matter composed of 2 or more elements in a fixed ratio properties differ from those of individual elements EX: salt (NaCl)
  15. Mixtures Variable combination of 2 or more pure substances. Homogeneous Mixture even distribution of components very small particles particles never settle EX: saline solution Kool-Aid
  16. Mixtures Heterogeneous Mixture Soup & Salad uneven distribution of components
  17. Mixtures Colloid medium-sized particles particles never settle EX: milk
  18. Mixtures Suspension large particles particles scatter light particles will settle (needs to be shaken) EX: fresh-squeezed lemonade
  19. Chemical Symbols Capitals matter! Element symbols contain ONE capital letter followed by lowercase letter(s) if necessary. Covs. CO Element (Cobalt) Compound (Carbon Monoxide )
  20. in a neutral atom Most of the atom’s mass. Subatomic Particles ATOM NUCLEUS ELECTRONS NEUTRONS PROTONS NEGATIVE CHARGE POSITIVE CHARGE NEUTRAL CHARGE Atomic Number equals the # of...
  21. Physical Property A characteristic of a substance that can be observed without changing its identity. can be used to separate mixtures EX: magnetism, density
  22. Physical Change A change in the form of a substance without changing its identity. properties remain the same reversible can be used to separate mixtures EX: dissolving, grinding
  23. Chemical Change A change in the identity of a substance. properties change irreversible Signs: color change, formation of a gas/solid, release of light/heat EX: burning, rusting
  24. Chemical Property A characteristic that indicates whether a substance can undergo a specific chemical change. EX: flammability, reactivity
  25. The Periodic Table

    History of the Periodic Table
  26. Dmitri Mendeleev Dmitri Mendeleev (1869, Russian) Organized elements by increasing atomic mass. Predicted the existence of undiscovered elements.
  27. Henry MoselyModern Periodic Table Henry Mosely (1913, British) Organized elements by increasing atomic number. Fixed problems in Mendeleev’s arrangement.
  28. Metallic Character Metals Nonmetals Metalloids
  29. B. Table Sections Representative Elements Transition Metals Inner Transition Metals
  30. Columns & Rows Group (Family) Period
  31. Terms Valence Electrons e- in the outermost energy level
  32. WAVES: A way to transmit energy
  33. Waves are defined as a periodic disturbance that carries energy from one place to another. A periodic disturbance is one that happens over and over again at regular intervals. . Like a bouncing ball, the motion repeats over and over again.
  34. There are two kinds of waves you should recognize. Longitudinal or compression waves and transverse waves.
  35. Longitudinal waves, like sound waves, are mechanical waves because they must have a material to travel through. The material they travel through is called the “medium”. The medium can be any material. Air Water Wood Rock Anything!
  36. Sometimes longitudinal waves are referred to as compression waves because they are caused by a vibrating object compressing and rarefying the atoms or molecules of the medium. Vibrating object Alternating areas of compression and rarefaction in the medium.
  37. By vibrating back and forth, the vibrating object alternates between compressing and rarefying the molecules of the medium.
  38. Areas of rarefaction are low pressure areas where the vibrating object pulls the molecules further apart. Areas of compression are high pressure areas where the molecules are squeezed closer together by a vibrating object.
  39. In longitudinal waves the molecules of the medium vibrate along with the vibrating object. Molecules of the medium vibrate back and forth on each side of a fixed resting point, transferring their kinetic energy to adjacent molecules. In this way the energy is transferred, but the molecules remain in place.
  40. Longitudinal waves get their name because the vibration that puts energy into the wave vibrates in the same plane in which the energy moves.
  41. Transverse Waves In a transverse wave the particle displacement is perpendicular to the direction of the energy transfer. The particles do not move along with the wave, they simply vibrate up and down about their individual rest positions as the wave passes by. Pick a single particle and watch its motion.
  42. The wavelengthof a wave is the distance between successive vibrations. Wavelength is measured in meters. Here is how wavelength is measured on a transverse wave.
  43. This diagram shows how wavelength can be measured on a longitudinal wave. It is measured from compression to compression.
  44. The Amplitudeof a wave determines how much energy a wave is carrying. This can easily be seen in a transverse wave where the wave height is the amplitude. Obviously, the higher the wave crest the higher the amplitude, and the greater the wave energy.
  45. In longitudinal waves amplitude is a measure of the degree of compression. The more compressed the compressions are the greater the amplitude. Low amplitude ( Less compression) High amplitude ( greater compression)
  46. Wave velocity is a measure of how fast the energy is being transferred. Wave velocity is measured in meters per second (m/s).
  47. Wavefrequency, for a transverse wave, is a measure of how many wave crests pass a point in one second. Wave frequency is measured in Hertz. 1Hertz is equal to 1wave per second. If 5 waves pass the smiley in one second, then the wave frequency is 5Hz or 5 waves per second. Longitudinal wave frequency is how many compressions pass a point in one second.
  48. Wave period, for transverse and longitudinal waves, is the time it takes for one complete wave ( one wavelength) to pass a point. If it takes .3seconds for a single wave to pass the smiley then the wave period is .3s. Wave period is measured in seconds.
  49. THE DOPPLER EFFECT AS IT APPLIES TO SOUND WAVES Moe hears a higher frequency Joe hears a low frequency
  50. Waves Two Types: Longitudinal Transverse
  51. C. Longitudinal Waves Longitudinal Waves (a.k.a. compressional) medium moves in the same direction as wave motion
  52. compression wavelength rarefaction wavelength C. Longitudinal Waves Wave Anatomy Amount of compression corresponds to amount of energy AMPLITUDE.
  53. 1 second Measuring Waves Frequency( f ) # of waves passing a point in 1 second Hertz (Hz) shorter wavelength  higher frequency  higher energy
  54. Speed of Sound 344 m/s in air at 20°C Depends on: Type of medium travels better through liquids and solids can’t travel through a vacuum Temperature of medium travels faster at higher temps
  55. Human Hearing sound wave vibrates ear drum amplified by bones converted to nerve impulses in cochlea
  56. Human Hearing Pitch highness or lowness of a sound depends on frequency of sound wave human range: 20 - 20,000 Hz ultrasonic waves subsonic waves
  57. Human Hearing Intensity volume of sound depends on energy (amplitude) of sound wave measured in decibels (dB)
  58. Medical Imaging SONAR “Sound Navigation Ranging” Seeing with Sound Ultrasonic waves - above 20,000 Hz
  59. A. EM Radiation Electromagnetic Radiation transverse waves produced by the motion of electrically charged particles does not require a medium speed in a vacuum = 300,000 km/s electric and magnetic components are perpendicular
  60. EM Radiation Photons tiny, particle-like bundles of radiation absorbed and released by electrons energy increases with wave frequency
  61. EM Spectrum long  low f low energy short  high f high energy
  62. Types of EM Radiation Radiowaves lowest energy EM radiation
  63. Types of EM Radiation Radiowaves FM - frequency modulation AM - amplitude modulation Microwaves penetrate food and vibrate water & fat molecules to produce thermal energy
  64. Types of EM Radiation Infrared Radiation(IR) slightly lower energy than visible light can raise the thermal energy of objects thermogram - image made by detecting IR radiation
  65. R O Y G. B I V red orange yellow green blue indigo violet Types of EM Radiation Visible Light small part of the spectrum we can see ROY G. BIV - colors in order of increasing energy
  66. Types of EM Radiation Ultraviolet Radiation (UV) slightly higher energy than visible light Types: UVA - tanning, wrinkles UVB - sunburn, cancer UVC - most harmful, sterilization
  67. Types of EM Radiation Ultraviolet Radiation (UV) Ozone layer depletion = UV exposure!
  68. Types of EM Radiation X rays higher energy than UV can penetrate soft tissue, but not bones
  69. Radiation treatment using radioactive cobalt-60. Types of EM Radiation Gamma rays highest energy EM radiation emitted by radioactive atoms used to kill cancerous cells
  70. Light and Matter Opaque absorbs or reflects all light Transparent allows light to pass through completely Translucent allows some light to pass through
  71. Seeing Colors The retina contains… Rods - dim light, black & white Cones - color red - absorb red & yellow green - absorb yellow & green blue - absorb blue & violet Stimulates red & green cones Stimulates all cones
  72. Mixing Colors Primary light colors red, green, blue additive colors combine to form white light EX: computer RGBs View Java Applet on primary light colors.
  73. Mixing Colors Filter transparent material that absorbs all light colors except the filter color View Java Applet on filters.
  74. Mixing Colors Pigment colored material that absorbs and reflects different colors Primary pigment colors cyan, magenta, yellow subtractive colors combine to form black EX: color ink cartridges
  75. C. Mixing Colors Light Pigment When mixing pigments, the color of the mixture is the color of light that both pigments reflect.
  76. Normal incident beam reflected beam Reflection Reflection when a wave strikes an object and bounces off
  77. Reflection Law of Reflection the angle of incidence equals the angle of reflection
  78. SLOWER FASTER Refraction Refraction bending of waves when passing from one medium to another caused by a change in speed slower (more dense) light bends toward the normal faster (less dense) light bends away from the normal
  79. Refraction Refraction depends on… speed of light in the medium wavelength of the light - shorter wavelengths (blue)bend more
  80. Refraction Example:
  81. Diffraction Diffraction bending of waves around a barrier longer wavelengths (red) bend more - opposite of refraction
  82. D. Interference Interference constructive  brighter light destructive  dimmer light
  83. Cool Applications! The “Broken Pencil” refraction
  84. E. Cool Applications! Diffraction Gratings glass or plastic made up of many tiny parallel slits may also be reflective spectroscopes, reflective rainbow stickers, CD surfaces
  85. Motion & Forces

    Motion Speed & Velocity Acceleration
  86. Newton’s First Law Newton’s First Law of Motion An object at rest will remain at rest and an object in motion will continue moving at a constant velocity unless acted upon by a net force.
  87. Reference point Motion Motion Motion Change in position in relation to a reference point.
  88. d v t Speed & Velocity Speed rate of motion distance traveled per unit time
  89. Speed & Velocity Instantaneous Speed speed at a given instant Average Speed
  90. Speed & Velocity Velocity speed in a given direction can change even when the speed is constant!
  91. vf - vi t a Acceleration Acceleration the rate of change of velocity change in speed or direction a: acceleration vf: final velocity vi: initial velocity t: time
  92. Acceleration Positive acceleration “speeding up” Negative acceleration “slowing down”
  93. Distance-Time Graph A B Graphing Motion slope = steeper slope = straight line = flat line = speed faster speed constant speed no motion
  94. Distance-Time Graph Graphing Motion Acceleration is indicated by a curve on a Distance-Time graph. Changing slope = changing velocity
  95. Motion & Forces

    Force & Acceleration Newton’s Second Law Gravity Air Resistance Calculations
  96. Newton’s Second Law Newton’s Second Law of Motion The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. F = ma
  97. F a m A. Newton’s Second Law F m F = ma F: force (N) m: mass (kg) a: accel (m/s2) 1 N = 1 kg ·m/s2
  98. Gravity Gravity force of attraction between any two objects in the universe increases as... mass increases distance decreases
  99. more mass less distance Gravity Who experiences more gravity - the astronaut or the politician? Which exerts more gravity - the Earth or the moon?
  100. Gravity Weight the force of gravity on an object W = mg W: weight (N) m: mass (kg) g: acceleration due to gravity (m/s2) MASS always the same (kg) WEIGHT depends on gravity (N)
  101. Gravity Would you weigh more on Earth or Jupiter? Jupiter because... greater mass greater gravity greater weight
  102. elephant feather B. Gravity Accel. due to gravity (g) In the absence of air resistance, all falling objects have the same acceleration! On Earth: g = 9.8 m/s2
  103. Air Resistance Air Resistance a.k.a. “fluid friction” or “drag” force that air exerts on a moving object to oppose its motion depends on: speed surface area shape density of fluid
  104. Is the following statement true or false? An astronaut has less mass on the moon since the moon exerts a weaker gravitational force. False! Mass does not depend on gravity, weight does. The astronaut has less weight on the moon.
  105. Newton’s Third Law For every action, there is an equal and opposite reaction.
  106. Other examples of Newton’s Third Law The baseball forces the bat to the left (an action); the bat forces the ball to the right (the reaction).
  107. 3rd Law The reaction of a rocket is an application of the third law of motion. Various fuels are burned in the engine, producing hot gases. The hot gases push against the inside tube of the rocket and escape out the bottom of the tube. As the gases move downward, the rocket moves in the opposite direction.
  108. - What Is Energy? Kinetic Energy Kinetic energy increases as mass and velocity increases.
  109. - What Is Energy? Potential Energy Gravitational potential energy increases as weight and height increase.
  110. - Energy Transformations and Conservation Energy Transformations Most forms of energy can be transformed into other forms.
  111. - Energy Transformations and Conservation Transformations BetweenPotential and Kinetic Energy A pendulum continuously transforms energy from kinetic to potential energy and back.
  112. - Energy and Fossil Fuels Use of Fossil Fuels Fossil fuels can be burned to release the chemical energy stored millions of years ago.
  113. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. The total potential and kinetic energy of the particles in an object is called a. mechanical energy. b. thermal energy. c. chemical energy. d. electrical energy.
  114. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 2) An example of something that stores chemical energy is a. lightning. b. a microwave. c. a match. d. light.
  115. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 3) What type of conversion is taking place when natural gas is used to heat water? a. chemical energy into thermal energy b. thermal energy into mechanical energy c. mechanical energy into electromagnetic energy d. electromagnetic energy into chemical energy
  116. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 4) When you rub your hands together on a cold day, you use friction to convert a. mechanical energy into thermal energy. b. thermal energy into nuclear energy. c. nuclear energy into electrical energy. d. electrical energy into electromagnetic energy.
  117. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 5) According to the Law of Conservation of Energy, when energy changes from one form to another form, the total energy of that system ___ a. increases. b. alternates. c. decreases. d. remains the same.
  118. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 6) What energy transformations take place in a Hydroelectric power plant? A) ME C EM T S B) E ME EM T C) ME E D) GPE KE ME E
  119. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 7) What are the energy transformations that take place in a coal burning power plant in order from the starting energy form to the end product? A) Electrical to Mechanical to Thermal to Chemical B) Chemical to Thermal to Mechanical to Electrical C) Mechanical to Thermal to Chemical to Electromagnetic D) Mechanical to Chemical to Thermal to Mechanical
  120. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 8) What type of energy transformations takes place during photosynthesis? A) Electromagnetic to Electromagnetic B) Electromagnetic to Thermal C) Electromagnetic to Chemical to Thermal D) Electromagnetic to Sound
  121. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 9) What energy transformations take place in the picture above in order from start to the end product?
  122. Multiple ChoiceIdentify the choice that best completes the statement or answers the question. 10) Which is not a renewable fuel source? A. Geothermal B. Coal C. Wood D. Solar
  123. Graphic Organizer Energy is the ability to do measured in exists as Potential energy Kinetic energy Joules Work which at a given rate is can be Gravitational Power Elastic
  124. What is thermal energy? S8P2d. Describe how heat can be transferred through matter by the collisions of atoms (conduction) or through space (radiation). In a liquid or gas, currents will facilitate the transfer of heat (convection).
  125. What is Thermal Energy?
  126. Kinetic Theory of Matter All matter is made of atoms and molecules that act like tiny particles. 2. These tiny particles are always in motion. The higher the temperature, the faster the particles move 􀃆 (The higher the temperature, the more KE due to speed at which the particles move) 3. At the same temperature, more massive (heavier) particles move slower than less massive (lighter) particles. (Mass and Velocity of particle movement are inversely proportional. If temp remains the same, mass will have to increase if velocity decreases and vice versa)
  127. Particles of matter are in constant motion. This motion relates directly to the state of matter of the object (solids, liquids, or gases). Temperature affects how fast these particles move. The higher the temperature the faster the particles move. Moving particles possess kinetic energy. Temperature is defined at the average kinetic energy of the particles of an object.
  128. Thermal Energy is the sum total of all of the energy of the particles of an object. Thermal energy and temperature are related though DIFFERENT. Temperature is the average kinetic energy of the particles of an object. Thermal energy is the total amount of energy of the particles of an object. A bathtub full of water at 100oF has more thermal energy than a thimble of water at 100oF. The temperature is the same but the total amount of energy is different. The bathtub has more energy.
  129. Transferring Thermal Energy How is Thermal Energy Transferred? YOU MUST KNOW THIS!!!!! Conduction – direct contact Convection – through a fluid Radiation – by electromagnetic waves
  130. What is heat transfer by conduction? Heat transfers as particles of an object increase their collisions as heated. These collisions transfer the heat energy through the object by colliding with nearby particles.
  131. What is heat transfer by convection? Heat is transferred through a substance through currents. This occurs in fluids (liquids AND gases) Convection currents are caused by heating of a liquid or gas, the liquid or gas rises, then cools and falls. This occurs in the mantle of the earth And in the atmosphere. Most of our weather patterns are the result of convection currents in the atmosphere.
  132. What is heat transfer by radiation? Radiation is heat transfer by electromagnetic waves. These wave may pass through all states of matter and also through NO matter – such as the vacuum of space. This energy is often called radiant energy. Radiant energy from the sun travels through the vacuum of until it reaches the earth.
  133. How is heat flow controlled? Insulators – a material which does not allow heat to pass through it easily. Some animals have good insulation to survive severe winters.
  134. Buildings and houses are insulated so that heat does not pass out of (winter time) and into (summer time).
  135. What are some other uses of insulation?
  136. Conduction is the transfer of energy by A) molecules bumping into each other B) the difference of density C) the traveling of waves D) convection currents moving
  137. 2) What is it called when cold air falls down and warm air pushes up? A) convection B) conduction C) radiation D) insulation
  138. 3) Which is the best example of conduction? You take a sip of hot soup and burn your tongue. B) Water in a well-built thermos takes hours to cool. C) You get a sun burn from sitting in the sun all day. D) You swim in a lake and notice in some areas, the water is warm but in others it's cold.
  139. 4) Which is the best example of convection? You get a sun burn from sitting in the sun all day. B) You take a sip of hot soup and burn your tongue. C) Water in a well-built thermos takes hours to cool. D) You swim in a lake and notice in some areas, the water is warm but in others it's cold.
  140. 4) Which is the best example of radiation? You get a sun burn from sitting in the sun all day. B) You take a sip of hot soup and burn your tongue. C) Water in a well-built thermos takes hours to cool. D) You swim in a lake and notice in some areas, the water is warm but in others it's cold.
  141. 5) The total energy of all the particles in a substance is called temperature. B. thermal energy. C. degrees. D. mass.
  142. 6) Heat, like work, is an energy transfer measured in watts. B. degrees. c. joules. d. kelvins.
  143. 7) The movement of thermal energy from a warmer object to a cooler object is called heat. B. temperature. C. motion. D . momentum.
  144. 8) A material that does NOT conduct heat well is called a(an) insulator. b. conductor. c. metal. d. radiator.
  145. 9) The addition or loss of thermal energy changes the arrangement of the particles during a change of state. b. conduction. c. convection. d. radiation.
  146. 10) Which of these is a good conductor? Wood b. Paper Silver d. Air
  147. 11) You have four containers of water. The water in each container is at the same temperature. Which container has the greatest thermal energy? a 5-mL container a 10-mL container a 15-mL container a 50-mL container
  148. Electric Currents An electric current is a flow of electric charges.
  149. A circuit is the path that is made for an electric current.
  150. Series Circuit A circuit that only has one path for current to flow through is called a series circuit.
  151. If the path is broken, no current flows through the circuit.
  152. Parallel Circuits A type of circuit that has more than one path for current is called a parallel circuit.
  153. If one part of the path is removed, the current continues to flow through the other paths of the circuit.
  154. Circuit symbols A battery (the correct name for this is a cell)
  155. Circuit symbols
  156. Circuit symbols A connector (or wire)
  157. Circuit symbols a bulb
  158. Circuit symbols An ammeter A
  159. Circuit symbols V
  160. Circuit symbols a voltmeter V
  161. Circuit symbols a resistor
  162. Electricity A. Electric Charge 1. Static electricity is the accumulation of excess electric charges on an object. a. More e¯ = negative charge b. More protons = + charge 2. Charge is conserved (e¯ move from one object to another).
  163. 3. Law of Charges a. Opposite charges attract. b. Like charges repel. 4. Electric fields a. Electric fields exert force on objects within the field. b. Weaker with distance.
  164. 5. Transferring electric charge a. Conductors: e¯ move easily. b. Insulators: hold e¯ tightly. c. Contact charging is done when two materials are rubbed together (best with insulators). d. Charging by induction is done when one charged object induces a charge on another.
  165. 6. Lightning a. Large static discharge between the earth and clouds. b. Lightning was found to be static electricity by Ben Franklin. 7. Grounding a. Conductive path to Earth. b. Lightning rods & plumbing.
  166. e. Wire resistance greater for: 1) Longer wires 2) Thinner wires 3) Higher temperatures
  167. C. Electrical Circuits 1. A circuit is a conducting path. 2. Series circuit a. One path b. Any break & all devices go out c. Current is the same throughout the circuit
  168. 3. Parallel circuit a. Multiple paths b. A break in one branch & the other branches stay on c. Voltage is the same in each branch, but current and resistance may be different
  169. Comparison of series and parallel circuits The same voltage battery Notice the brightness of the bulbs
  170. - What Is Magnetism? Magnetic Fields Magnetic field lines spread out from one pole, curve around the magnet, and return to the other pole.
  171. - What Is Magnetism? Magnetic Fields When the magnetic fields of two or more magnets overlap, the result is a combined field.
  172. - Inside a Magnet The Atom An atom contains neutrons and positively charged protons in its nucleus. Negatively charged electrons move randomly throughout an atom.
  173. - Inside a Magnet Magnetic Domains In a magnetized material, all or most of the magnet domains are arranged in the same direction.
  174. - Inside a Magnet Making and Changing Magnets Each piece of a magnet retains its magnetic properties after it is cut in half.
  175. - Magnetic Earth Earth as a Magnet Just like a bar magnet, Earth has a magnetic field surrounding it and two magnetic poles.
  176. Graphic Organizer Magnets produce have atoms grouped in Magnetic fields strongest at mapped by Magnetic domains Magnetic field lines The poles
  177. The End