University:
Eastern Kentucky University
Course:
PHY 131 | College Physics I
Academic year:

2020
Views:

349

Pages:

1
Author:

levedzgetmo7f

Physics and Math 2: Work and Energy Energy Work Structural Proteins: The property of a system that enables it to do something or make something happen, including the capacity to do work. SI units are joules (J). J= !"#•#$% &% Work: The process by which energy is transferred from one system to another. Can be expressed as the dot product of force and displacement: 𝑊 =𝐹##𝑑=𝐹#𝑑#cos#(q ) Power: The rate at which work is done or energy is transferred. SI Kinetic Energy: Energy associated with the mvmt of objects. It ' depends on mass and speed squared. KE = m v2 ( Potential Energy: Energy stored within a system. Gravitational Related to the mass of an object and its height Potential Energy: above a zero point. 𝑈 =𝑚#𝑔#ℎ Elastic Potential Related to the spring constant and the degree of Energy: stretch or compression of a spring squared. ' 𝑈 =# #𝑘#𝑥 ( ( Electrical Potential The energy between two charged particles. Energy: Chemical Potential The energy stored in the bonds of compounds. Energy: Conservative Forces: Path independent and do not dissipate the mechanical energy of a system. Examples: Gravity and electrostatic forces. Nonconservative Path dependent and cause dissipation of mechanical Forces: energy from a system. Examples: Friction, air resistance, and viscous drag. 8 unit is watt (W). W = 9 = :##; 9 = <=##; % 9> Work-Energy When net work is done on or by a system, the system’s Theorem: kinetic energy will change by the same amount. 𝑊?@A=# D𝐾 =𝐾C −𝐾E Mechanical Advantage Mechanical The factor by which a simple machine multiplies the Advantage: input force to accomplish work. The input force necessary to accomplish the work is reduced and the distance through which the reduced input force must be applied is increased by the same factor. MA of an Inclined MA=#H@?"AI#JC#E?KLE?@ M@E"IA#JC#E?KLE?@ Plane: Simple Machines: Inclined plane, wedge, wheel and axle, lever, pulley, and screw. Efficiency: The ratio of the machine’s work output to work input when nonconservative forces are taken into account. X Mechanical#Advantage=# XYZ[ \]