Work, Energy and Power Flashcards
Define Work Done (scalar), W
Work done is defined as the product of the force and the distance moved in the direction of the force.
SI unit for Energy and Work Done
J (Joule)
Formula of Work Done
W = F x s
One joule is defined as…
the work done by a force of one newton which moves an object through a distance of 1 meter in the direction of the force.
Define Energy (scalar)
The capacity to do work
Define Kinetic Energy
Energy possessed by objects in motion
Define Gravitational Potential Energy
Energy which an object possesses because of it’s position relative to the ground.
Formula of kinetic energy
KE= ½mv²
Formula for Gravitational Potential Energy
GPE= mgh
State the Principle of Conservation of Energy
Energy cannot be created or destroyed but only converted from one form to another; the total energy in an insolated system remains constant.
Define Power (scalar)
Power is the rate of doing work
Si unit of Power
W (watt)
Formula for power
Power= Work/Time = change in energy/Time = Force x Velocity
One watt is defined as…
the power delivered when one joule of work is done in one second or one joule of energy is converted in one second.
Define Effeciency
the percentage of useful work output divided by the total work input
