University:
California State University, Northridge
Course:
ME 101/L | Introduction to Mechanical Engineering and Lab
Academic year:

2024
Views:

497

Pages:

18
Author:

Cory Singh

Chapter 18 Engineering Fundamentals 18.1 Statics   Concerned with equilibrium of bodies subjected to force systems The two entities that are of the most interest in statics are forces and moments. 18.1 Statics  Force:    The manifestation of the action of one body upon another. Arise from the direct action of two bodies in contact with one another, or from the “action at a distance” of one body upon another. Represented by vectors 18.1 Statics  Moment:   Can be thought of as a tendency to rotate the body upon which it acts about a certain axis. Equilibrium:  The system of forces acting on a body is one whose resultant is absolutely zero 18.1 Statics  Free Body Diagrams (FBD):  Neat sketch of the body showing all forces and moments acting on the body, together with all important linear and angular dimensions. 18.2 Dynamics  Separated into two sections:  Kinematics   Study of motion without reference to the forces causing the motion Kinetics  Relates the forces on bodies to their resulting motions 18.2 Dynamics  Newton’s laws of motion:     1st Law – The Law of Inertia 2nd Law – F=ma 3rd Law – Fab=-Fba Law of Gravitation 18.3 Thermodynamics  Involves the storage, transformation and transfer of energy.    Stored as internal energy, kinetic energy, and potential energy Transformed between these various forms Transferred as work or heat transfer 18.3 Thermodynamics  There are many definitions, laws, and other terms that are useful to know when studying thermodynamics. 18.3 Thermodynamics  A few useful definitions:  System   Control Volume (open system)   A fixed quantity of matter A volume into which and/or from which a substance flows Universe  A system and its surrounding 18.3 Thermodynamics  Some Laws of ideal gases:  Boyle’s Law   Charles’ Law   Volume varies inversely with pressure Volume varies directly with temperature Avagadro’s Law  Equal volumes of different ideal gasses with the same temperature and pressure contain an equal number of molecules 18.4 Electrical Circuits  Interconnection of electrical components for the purpose of:    Generating and distributing electrical power Converting electrical power to some other useful form Processing information contained in an electrical form 18.4 Electrical Circuits     Direct Current (DC) Alternating Current (AC) Steady State Transient circuit 18.4 Electrical Circuits Quantity Symbol Unit Charge Q coulomb Current I ampere Voltage V volt Energy W joule Power P watt 18.4 Electrical Circuits  Circuit Components:     Resistors Inductors Capacitors Sources of Electrical Energy   Voltage Current 18.4 Electrical Circuits  Kirchhoff’s Laws    Kirchhoff’s Voltage Law (KVL) Kirchhoff’s Current Law (KCL) Ohm’s Law  V=IR 18.4 Electrical Circuits   Reference Voltage Polarity and Current Direction Circuit Equations     Using Branch Currents Using Mesh Currents Circuit Simplification DC Circuits 18.5 Economics  Value and Interest     The value of a dollar given to you today is of greater value than that of a dollar given to you one year from today Cash Flow Diagrams Cash Flow Patterns Equivalence of Cash Flow Patterns