Power Flashcards
(13 cards)
Definition of work (done)
The product of force (N) and displacement
Explanation of work
Done when an applied force displaces an object though displacement
Unit for work
Joules (J) or Nm
Unit of power
J/s or Watt (w)
Power equation
P = W (work done)/time period
Or
P = E (energy transferred)/time period
Energy stores
Kinetic, gravitational, elastic, magnetic, electrostatic, chemical, nuclear, thermal
Energy transfers
Mechanical, electrical, heating, radiation
Definition of power
Work done per unit time
Energy transferred per unit time
Explanation of power
The work done (w) divided by the time is took (t)
Main source of energy
Radiation from the sun is the main source of energy for all our energy resources except geothermal, nuclear and tidal
How is energy released from the sun
Nuclear fusion
How is energy released in nuclear reactors
Nuclear fission
Efficiency equation
Useful energy output/total energy input * 100
