Conservation of energy

• What is the conservation of energy principle?

  Energy can be transferred, stored, or dissipated
• What does the conservation of energy principle imply about energy?

  Energy cannot be created or destroyed
• How does charging a phone illustrate the conservation of energy principle?

  Electrical energy converts to chemical energy
• What happens to chemical energy when you use your phone?

  It converts back to electrical energy
• What type of energy conversion occurs in the phone's screen?

  Electrical energy to light energy
• What type of energy conversion occurs in the phone's speaker?

  Electrical energy to sound energy
• What is the ideal outcome when energy is transferred?

  All energy is transferred usefully
• What is wasted energy typically in the context of a phone?

  Generally in the form of heat
• What happens to your phone when it charges or is used a lot?

  It may warm up due to wasted energy
• What is a system in physics?

  A portion of the physical universe analyzed
• What is the environment in relation to a system?

  Everything outside the chosen system
• Why is a phone considered an open system?

  Energy and matter can move freely
• What happens when a phone gets hot in an open system?

  It gives out heat energy to surroundings
• What defines a closed system in physics?

  Energy and matter cannot enter or escape
• What happens to heat energy in a closed system with a phone?

  It dissipates to the air inside the jar
• What does it mean for the overall energy of a closed system?

  It doesn't ever change
• What are the key concepts of the conservation of energy principle?

  • Energy can be transferred, stored, or dissipated
  • Energy cannot be created or destroyed
  • Energy moves between different objects and forms
• What are the differences between open and closed systems?

  Open System:

  • Energy and matter can move freely
  • Example: Phone charging

  
  

  Closed System:

  • Energy and matter cannot enter or escape
  • Example: Phone in a sealed jar