Mechanical Engineering Exam 1 Latest Update Graded A+

Mechanical Engineering Exam 1 Latest Update Graded A+ Machine -A device that uses energy to do work to accomplish some desired activity -They do not produce energy, but they do transmit and transform energy -Machines can transmit a force, control its motion, and change its direction -A machine is a system of components Component A small piece that makes up a larger whole. Each component is there for a specific job, but the sum of components System A combination of components Mechanical Engineering -The designing of machines that contribute to society and our quality of life -Mechanical engineers apply the principles of mathematics, chemistry, and physics to solve real- world problems Dimension -Describes a physical property of anything -What we are measuring Base Dimensions -Are independent of other dimensions -They are limited in number -length, mass, time, temperature, force Derived Dimension -Derived from, or composed of, base dimensions i.e. Area (length x width), Weight (mass x acceleration), velocity (length/time) System International (SI) The standard system of units that uses base 10 and used in the rest of the world. -US does not use, but Great Britain does -Base Units: mass-kilograms (kg), length-meters (m), and time-Seconds (S) -Force is a derived unit measured in newtons (N) US Customary A system adopted from an old British system of units in the 13th century -Engineering system -Units: length-foot (ft), time-second (s), force-(lbs) -Mass is a derived unit called a slug -Political/Economic choice -Awkward Length The magnitude of something in a particular direction Mass -The amount of atoms and molecules in something -Matter is energy that has become solid -An object gains mass when it gains more energy and vice a versa -Units: SI-kgs and USA: Slugs, lbs Temperature An indication of kinetic energy of mass at the molecular level Area -A flat, two dimensional property -Units of length multiplied by length describe area -A=length x width Volume -Three-dimensional property measured in units of length times length times length -V=length x width x height Units for Pressure -psi -newtons -pascals