equations

• kinetic energy =

  0.5 x mass x (speed)2
• gravitational potential energy = 


  mass x gravitational field strength x height
• power =


  energy transferred divided by time
• Kinetic energy


  0.5 × mass × (speed)^2
• Elastic potential energy


  0.5 × spring constant × (extension)^2
• Gravitational potential energy


  mass × gravitational field strength × height
• Change in thermal energy

  mass × specific heat capacity × temperature change
• Power


  energy transferred / time
• Power


  work done / time
• Efficiency


  useful output energy transfer / total input energy transfer
• Efficiency


  useful power output / total power input
• Charge flow


  current × time
• Potential difference

  current × resistance
• Power


  potential difference × current
• Power


  (current)^2 × resistance
• Energy transferred


  power × time
• Energy transferred


  charge flow × potential difference
• Density


  mass / volume
• Thermal energy for a change of state

  mass × specific latent heat
• Weight


  mass × gravitational field strength
• Work done


  force × distance (along the line of action of the force)
• Force

  spring constant × extension
• Moment of a force

  force × distance (normal to direction of force)
• Pressure


  force normal to a surface / area of that surface
• Pressure due to a column of liquid

  height of column × density of liquid × gravitational field strength
• Distance travelled


  speed × time
• Acceleration


  change in velocity / time taken
• Relationship between final velocity, initial velocity, acceleration and distance

  (final velocity)^2 - (initial velocity)^2 = 2 × acceleration × distance
• Resultant force


  mass × acceleration
• Momentum


  mass × velocity
• Force


  change in momentum / time taken
• Period


  1 / frequency
• Wave speed


  frequency × wavelength
• Magnification


  image height / object height