Energy Transfers in a System

• energy can be transferred usefully, stored or dissipated, but cannot be created or destroyed
• energy transfers within a closed system will always equal net zero
• dissipated energy is wasted
• investigating methods of insulation -

  • place a small beaker into a large beaker
  • fill the small beaker with hot water from a kettle
  • put a piece of cardboard over the beakers as a lid. the lid should have a hole suitable for a thermometer
  • record the demo of the water in the small beaker and start the stopwatch
  • records the water temp every 2 mins for 20 mins
  • repeat, each time packing the space between the large and small beaker with the chosen insulating material
  • plot a graph with temp = y and time = x
• ways to increase efficiency-

  • thermal insulation
  • lubrication
  • streamlining