Energy stores and systems

• 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 is kinetic energy associated with?

  Kinetic energy is associated with the movement or motion of an object.
• 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?

  Elastic potential energy is the energy held in an already stretched spring.
• What is chemical energy?

  Chemical energy is held in chemical bonds.
• What is magnetic energy?

  Magnetic energy is what holds magnets to your fridge.
• What is electrostatic energy?

  Electrostatic energy is what occasionally gives you a shock when you touch your car.
• What is nuclear energy?

  Nuclear energy is what we get from breaking atoms apart.
• How can energy be transferred between different forms?

  Energy can be transferred mechanically, electrically, by heating, or by radiation.
• What is a system in physics?

  A system is a collection of matter that we consider when analyzing energy transfer.
• What happens in an open system?

  In an open system, matter can exchange energy with the outside world.
• What is a closed system?

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

  In a closed system, the overall change in energy is always zero.
• How does energy transfer occur when using a kettle?

  1. Electrical energy flows from the plug socket to the kettle's heating element.
  2. This energy is transferred to the thermal energy store of the heating element.
  3. The heating element then transfers energy to the water's thermal energy store.
• What is another way of saying energy transferred?

  Energy transferred can also be referred to as work done.
• What are the two main types of work done?

  • Mechanical work done
  • Electrical work done
• What does mechanical work done involve?

  Mechanical work done involves using a force to move an object.
• Give an example of mechanical work done.

  Kicking a ball up in the air is an example of mechanical work done.
• What does electrical work involve?

  Electrical work is done when current flows and overcomes resistance in the wires of a circuit.
• How does friction do work in the example of a train crossing a broken bridge?

  Friction slows the train down by transferring energy from the wheels' kinetic energy stores to the thermal energy stores of the surroundings.
• What is the relationship between work done and energy transfer?

  • Work done is another term for energy transferred.
  • It can occur mechanically or electrically.