Work and Power Flashcards
(11 cards)
When energy is transferred
work is done.
The work done is equal to the amount of energy transferred.
work done =
force × distance moved
W = F × d
When an object is lifted
it gains energy in its gravitational store.
Change in the gravitational potential energy store =
mass × gravitational field strength × change in height
Ep = m × g × ∆h
When an object moves faster
it gains energy in its kinetic store.
kinetic energy =
½ x mass x speed2
EK = ½ m v2
A system is
an object or group of objects.
If no energy is transferred to other stores
a falling object will transfer all of its gravitational store to its kinetic store. A rising object will transfer all of its kinetic store to its gravitational store.
Power is the
rate of transfer of energy or the rate of doing work.
The more energy that is transferred each second
the greater the power.
work done =
power x time taken
W = P x t
