Energy Stores

• Specific heat capacity

  The amount of energy needed to increase the temperature of 1kg of that substance by 1°C
• Object thrown upwards

  1. Decreases kinetic

  2. Increases gravitational potential
• Moving object hitting a wall

  1. Decreases kinetic

  2. Increases thermal
• Bow releasing arrow

  1. Decreases elastic potential

  2. Increases kinetic
• Vehicle braking

  1. Decreases kinetic

  2. Increases thermal (friction)
• Heating water

  1. Decreases chemical

  2. Increases thermal
• Using battery fan

  1. Decreases chemical

  2. Increases kinetic & thermal (motor)
• Electric scooter

  Chemical energy in battery transferred to kinetic energy store of the scooter and thermal energy from friction between wheels & ground
• Gravitational potential energy

  • Increases when object goes up
  • Decreases when object goes down
• Kinetic/elastic/gravitational energy measured in Joules (J)
• Best conductors of thermal energy: Metal
• Best insulators of thermal energy: Wool & glass
• Higher the thermal conductivity

  Higher rate of energy
• Thick layer of insulation

  Low energy transfer rate
• Thermal energy transfers


  From a warmer place to a colder place
• Efficiency

  Shows how much of the total energy transferred is transferred to useful or less useful energy stores, or wasted
• Uncertainty 


  Range of values divided by 2