Chapter 5 Work, Energy and Power Flashcards
What is the equation for work done?
Work = Force x Distance moved in the direction of the force
What is work done?
Energy Transferred
How can you calculate work done at an angle?
Use triganometry
Name all the forms of energy and what they are
Kinetic - Motion
Gravitational - Energy based off gravitational fields
Chemical - Energy in the bonds
Elastic potential - Based off energy of the change in the shape of an object
Electrical potential - Based off the position of charges in an electric field
Nuclear - Energy in the nuclei of atoms
Radiant - EM Waves
Sound - Movement of atoms
Internal - Heat or thermal energy
What is the principle of the conservation of energy?
This is the principle that energy cannot be created or destroyed ( so the total energy in a closed system is conserved) and can only transformed from one type to another
What is the equation of kinetic energy?
Ke = 1/2mv^2
What is the equation for gravitational potential energy?
GPE = mgh
What is the equation for gravitational potential energy similar to?
The work done equation
WD = Force x Distance moved in a direction
GPE = (mg) x h
What equation can be when an object is dropped from a height? What are the assumptions?
mgh = 1/2mv^2
There are no resistive forces
What is power?
It is a measure of the rate of work done
What is the power equation?
P = W / T Power = Work / Time
What are the other equations for power?
Power = (Force x Distance) / Time
so
Power = Force x Velocity
because distance / time is velocity
What is efficiency in terms of energy in a closed system?
It is a measure of how much of the energy inputted is outputted as usefull energy
What is the equation for efficiency
( Useful output energy / total input energy ) x 100
