Power and efficiency



Before watching this video, please ensure that you have understood the following topics:

  • Specific heat capacity and specific latent heat (Matter)
  • Forces, motion and work donePower; Gravity (Forces)
  • Power and energy transfers (Electricity)
  • Work done (Energy)

The problem with energy is that there’s only so much of the stuff to go round.  In this important video, we’ll look at the meaning of the Principle of Conservation of Energy, before going on to describe the various ways in which useful energy can be dissipated from a system and the steps which can be taken to minimise such ‘wasted’ energy.

Later in the video, we’ll look at a few examples on the use of both forms of the equation for the efficiency of an energy transfer, before going on to discuss another practical activity in which the effectiveness of a number of different thermal insulators is investigated.

Please note that this video includes some higher tier-only content.

Key Words

categoric variable, energy, practical activity, resolution, PAG, power, energy transfer, conservation of energy, dissipate, dissipation, closed system, thermal conductivity, insulation, lubrication, streamlining, friction, efficiency, insulator