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Chapter Basic Theories and Math Matter • All matter consists of atoms • Atomic structure – Protons • Are positively charged particles – Electrons • Are negatively charged particles – Neutrons • Have no electrical charge States of Matter (cont’d) • By adding or removing heat, matter can change states Mass and Weight • Mass – Is the amount of matter in an object – Size is related to mass • Weight – Is a force measured in pounds or grams – Is caused by gravitational pull Size • An object’s size is related to its mass • Size dimensions are typically stated by length, width, and height • Volume is the product of all three Formulas • Circumference – Diameter times Pi (3.14) • Volume – Length times width times height • Area of a Circle – Pi (3.14) times the radius squared Proportions • Ratios can also be expressed as proportions • Coolant is often mixed 50% water and 50% coolant This is a 1:1 ratio • The air/fuel mixture is typically 14.7:1 This means 14.7 parts of air are mixed with part of fuel Force • Force can be applied to objects by direct contact or from a distance • Forces can be applied from any direction and with any intensity • When two or more forces are applied to an object, the combined force is called the resultant Automotive Forces • Balanced forces are in equilibrium • Turning forces can cause an object to rotate • Centrifugal and centripetal forces are either away from or towards the center of a circle • Pressure is a force applied against an object and measured in unit of force per unit of surface area Motion • When forces on an object not cancel out, they will change the object’s speed, direction or motion, or both • The resistance to change is called inertia • When a forces overcomes inertia, the object gains momentum Methods of Heat Transfer • Convection – Transfer of heat by movement of a heated substance • Conduction – The movement of heat through a material • Radiation – The transfer of heat by infrared waves The pH Scale • Used to measure how acidic or basic a solution is • Scale is from to 14 • Distilled (pure) water is • Acids are between and • Bases are between and 14 Reduction and Oxidation (Redox) • Oxidation is when a substance combines with oxygen • Rapid oxidation produces heat • The addition of hydrogen atoms or electrons is reduction • Both occur simultaneously • Redox is any reaction in which electrons are transferred Electrochemistry • The relationship between electricity and chemical change • Electrolysis uses current flow through a substance to cause a chemical change • Electrolyte is a substance that conducts current as a result of breaking down its molecules into positive and negative ions Electricity and Electromagnetism • All electrical effects are caused by electrical charges – positive and negative • Protons carry a positive charge • Electrons carry a negative charge • Electricity and magnetism are intertwined and inseperable Electricity • An electrical circuit is a path in which electrical current flows • A circuit is complete when electron movement (current flow) is possible Electrical Terms • Voltage – The strength of an electrical force • Amperes – The flow of electrons • Resistance – The opposition to electron flow Magnets • Some materials are natural magnets – most magnets are produced • A magnet has its atoms oriented along magnetic lines • All magnets have a North and South pole • A magnetic field exists between the poles Electromagnetism • A magnetic field is generated around a current carrying conductor • Increasing the current increases the strength of the magnetic field Producing Electrical Energy • Moving a conductor through a magnetic field produces electricity • This is how the vehicle’s generator and power generation plants produce electricity 29.7 psia Pounds per square inch gauge 15 psi 24.7 psia 10 psi 19.7 psia psi 14.7 psia psig 0” 10 psia 10” psia 20” Pounds per square inch absolute Vacuum ... Used to measure how acidic or basic a solution is • Scale is from to 14 • Distilled (pure) water is • Acids are between and • Bases are between and 14 Reduction and Oxidation (Redox) • Oxidation... advantage • Pressures and mechanical advantage are mathematically computed Sample Hydraulic System Gases • A gas is a fluid made up of particles that are in constant, random motion • Gases fill... breaking down its molecules into positive and negative ions Electricity and Electromagnetism • All electrical effects are caused by electrical charges – positive and negative • Protons carry a positive