PHYS 2070 Chapter Four and Five Notes
PHYS 2070 Chapter Four and Five Notes PHYS 2070
Popular in General Physics 1
Popular in Physics 2
This 8 page Class Notes was uploaded by chelsea1023 on Tuesday September 22, 2015. The Class Notes belongs to PHYS 2070 at University of Toledo taught by Dr. Scott Lee in Summer 2015. Since its upload, it has received 44 views. For similar materials see General Physics 1 in Physics 2 at University of Toledo.
Reviews for PHYS 2070 Chapter Four and Five Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/22/15
Chapter Four Force 0 Vector 0 Push or pull on object 0 Can be contact physical contact or field between disconnected objects force Newton s First Law 0 Object at rest stays at rest unless acted upon by a force 0 Object in motion stays in motion unless acted upon by a force 0 Net force is sum of all forces External force force that results from interaction of object and its environment Internal force forces from within the object can t change velocity Inertia tendency of object to continue in original motion Mass 0 Measure of the amount of stuff in an object 0 Larger mass less acceleration 0 Measured in kg 0 Scalar o Inherent property Newton s Second Law o Acceleration is directly proportional to net force and inversely proportional to mass of object 0 Can be used in 3D 0 Vector equation Units of Force 0 Newton N kg ms 2 o 1 N 0225 lb Force change in motion Weight 0 Amount of gravity acting on an object o W mg g gravity 980 msAZ 0 Not an inherent property 0 Depends on gravity Newton s Third Law 0 If two objects interact the force given to 2 by 1 is equal in magnitude but opposite in direction of the force given to 1 by 2 0 Single isolated force can t exist 0 Action and reaction forces act on different objects Applications of Newton s Laws 0 Assumes objects behave as particles 0 Mass string ropes are ignored 0 Interested in forces acting on object only 0 Ignore friction of rope o Tension magnitude of force on rope o Tension is same throughout rope Free Body Diagram 0 Identify all forces acting on object 0 Choose coordinate system Steps To Solving Newton s Second Law Problems 0 Draw free body diagram 0 Apply second law 0 Solve for unknown Equilibrium 0 Object at rest or moving at constant speed 0 Net force 0 0 Doesn t mean not moving means not accelerating Inclined planes 0 Choose coordinate system 0 Replace gravity with its separate components Forces of Friction 0 Friction is the resistance of an object and the surface it moves across 0 Proportional to normal force 0 Static gt kinetic o Direction is opposite of direction of motion 0 Static friction keeps object from moving 0 Kinetic friction acts when object is in motion Chapter Five Forms of Energy 0 Mechanical can be kinetic or potential 0 Chemical 0 Electromagnetic 0 Nuclear Energy can t be created or destroyed but can change form Work 0 Link between force and energy 0 Work product of component of force direction of displacement and magnitude displacement o WFdeltaX o WFcos rdeltaX o No information about time o Scalar 0 Units of work are joule J o Joule Newtons Meters o Joule kgm 2s 2 0 Work is 0 when force is perpendicular to displacement displacement is horizontal force is vertical 0 Total work sum of all work done by forces 0 Can be or 0 Positive force and displacement in same direction 0 Negative force and displacement in different direction 0 Doesn t happen on its own 0 Can be done by friction Kinetic Energy Energy of motion Scalar KE 12mv 2 Related to work Work Kinetic Energy Theory 0 If only change in object is speed work change in kinetic energy 0 Wnet KefKeideltaKE Kinetic energy is also amount of work required to bring a moving object to rest Types of Forces 0 Conservative 0 Work and energy can be recovered o Depends on initial and final positions of object 0 Ex Gravity spring force electromagnetic force 0 Potential energy 0 Nonconservative 0 Work done can t be recovered 0 Kinetic friction and air resistance Potential Energy 0 Associated with position of object 0 Property of system not object 0 Associated with every conservative force Gravitational potential energy associated with position of object in space near earth s surface 0 PEmgy o WgravityPEiPEf Work Energy Theory o Wnc KEfKEiPEfPEi Location with gravitational potential energy0 must be part of every problem Conservation of Mechanical Energy 0 Conserved number value of quantity is constant throughout any process although quantities may change form 0 Total mechanical energy remains constant Total mechanical energy sum of kinetic and potential energies Problem Solving with Conservation of Energy Define system 0 Select location of zero gravitational potential energy 0 Identify points of interest 0 Apply conservation of energy equation to system 0 Solve for unknown Potential Energy in a Spring 0 Hooke s law o F kX o F is restoring force 0 F is opposite direction of x o X is amount spring stretched o K is how spring was formed 0 Elastic potential energy 0 Related to work required to compress spring 0 PE of spring is added to both sides of equation
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'