1. energy

• What is the principle regarding energy as stated in the video?


  Energy is never created or destroyed; it is only transferred between different forms and objects.
• What are the different forms of energy mentioned in the video?

  • Thermal or internal energy
  • Kinetic energy
  • Gravitational potential energy
  • Elastic potential energy
  • Chemical energy
  • Magnetic energy
  • Electrostatic energy
  • Nuclear energy
• What is thermal or internal energy related to?


  It is related to the heat energy trapped within an object and its temperature.
• What type of energy is associated with the movement of an object?


  Kinetic energy.
• What is gravitational potential energy?


  It is the energy that an object possesses because of its position in a gravitational field.
• What is elastic potential energy?


  It is the energy held in an already stretched spring.
• What type of energy is held in chemical bonds?

  Chemical energy.
• What is magnetic energy?


  It is the energy that holds magnets to your fridge.
• What is electrostatic energy?


  It is the energy that can give you a shock when you touch your car.
• What is nuclear energy?


  It is the energy obtained from breaking atoms apart.
• How can energy be transferred between different forms?

  • Mechanically (e.g., stretching an elastic band)
  • Electrically (e.g., plugging into a socket)
  • By heating
  • By radiation (e.g., light or sound waves)
• What is meant by the term 'system' in physics?


  A system refers to a collection of matter being considered for energy transfer analysis.
• What happens to energy in an open system?


  Energy can be exchanged with the outside world, allowing the system to gain or lose energy.
• How does a closed system differ from an open system?


  A closed system is separate from the outside world, so neither matter nor energy can enter or leave.
• What happens when energy is transferred in a kettle example?

  1. Electrical energy flows to the kettle's heating element.
  2. It is transferred to the thermal energy store of the heating element.
  3. The heating element transfers energy to the water's thermal energy store.
• What does 'work done' refer to in energy transfer?


  'Work done' refers to the transfer of energy when a force is applied to move an object.
• What are the two main types of work done?


  Mechanical work and electrical work.
• What is mechanical work done?


  It involves using a force to move an object.
• What is electrical work done?


  It is done when current flows and energy is required to overcome resistance in wires.
• How does friction do work in the example of a train crossing a broken bridge?


  • Friction between brakes and wheels slows the train down.
  • Energy in the wheels' kinetic energy stores is transferred to the thermal energy stores of the surroundings.
• power = rate at which energy is transferred or used up
• a joule is equal to one newton metre
• the SI unit of energy is joules (J)
• This principle is known as the law of conservation of energy and is a fundamental concept in physics.
• The total energy in a closed system remains constant over time, even though it can change forms.
• Energy can neither be created nor destroyed, only transformed from one form to another.
• energy is the ability to do work