PHYSICS: Energy

• What does the term 'energy' refer to in the context of energy stores?

  Energy refers to the capacity for doing work
• What are the types of energy stores?

  • Magnetic
  • Thermal
  • Chemical
  • Kinetic
  • Electrostatic
  • Elastic potential
  • Gravitational potential
  • Nuclear
• What is the principle of conservation of energy?

  Energy cannot be created or destroyed, only transferred or stored
• What is an example of magnetic energy store?

  Fridge magnets
• How does internal (thermal) energy relate to temperature?

  In hotter objects, particles have more internal energy and vibrate faster
• What is an example of chemical energy store?

  Foods
• What does kinetic energy refer to?

  Kinetic energy refers to the energy of a moving object
• What is an example of electrostatic energy store?

  Thunderclouds
• What is elastic potential energy?

  Elastic potential energy is stored when an object is stretched or squashed
• What is an example of gravitational potential energy store?

  Aeroplanes
• What does nuclear energy refer to?

  Nuclear energy is stored in the nucleus of an atom
• What are some examples of nuclear energy applications?

  Uranium nuclear power and nuclear reactors
• What are the descriptions and examples of each type of energy store?

  • **Magnetic**: Energy stored when poles are moved; Examples: Fridge magnets, maglev trains.
  • **Internal (thermal)**: Total energy of particles; Examples: Human bodies, hot coffees.
  • **Chemical**: Energy in chemical bonds; Examples: Foods, muscles.
  • **Kinetic**: Energy of moving objects; Examples: Runners, buses.
  • **Electrostatic**: Energy from charges; Examples: Thunderclouds, Van De Graaff generators.
  • **Elastic potential**: Energy when stretched/squashed; Examples: Catapults, springs.
  • **Gravitational potential**: Energy at height; Examples: Aeroplanes, kites.
  • **Nuclear**: Energy in atomic nucleus; Examples: Uranium power, reactors.
• What is the main concept of energy in terms of storage?

  Energy can be transferred, dissipated, or stored in different ways.
• How does energy behave according to the law of conservation?

  Energy cannot be created or destroyed.
• What happens to energy when a system changes?

  There is a change in the way some or all of the energy is stored.
• What is an example of energy transfer involving kinetic energy?

  A swinging pirate ship ride transfers kinetic energy into gravitational potential energy.
• How is chemical energy transferred in a boat's movement?

  The boat pushes through the water as chemical energy is transferred into kinetic energy.
• What occurs in an electric kettle when water is brought to a boil?

  Electricity increases the internal energy of the element, raising the thermal energy of the water.
• What is the definition of 'doing work' in a scientific context?

  Doing work means that energy has been transferred.
• What are the four types of energy transfer?

  • Mechanical work: a force moving an object through a distance
  • Electrical work: charges moving due to a potential difference
  • Heating: due to temperature difference
  • Radiation: energy transferred as a wave
• What is the potential difference in an electrical context?

  The potential difference is a measure of the energy given to charge carriers in a circuit.
• What happens to energy when it is emitted from a material?

  The internal energy of the material decreases when energy is emitted.
• How do transfer diagrams represent energy transfers?

  • Boxes show energy stores (e.g., chemical, kinetic, gravitational potential)
  • Arrows indicate energy transfers (e.g., heating, by waves, electric current)
• What does a transfer diagram for a child at the top of a slide illustrate?

  It shows gravitational energy being transferred as mechanical work to speed up against friction.
• What is a Sankey diagram used for?

  • It shows how energy in a system is transferred into different stores.
  • The width of the arrows represents the amount of energy.
• What is gravitational potential energy?

  Gravitational potential energy is the energy stored by an object lifted against the force of gravity.
• What happens to energy during the transfer from gravitational potential energy to kinetic energy?

  Energy shifts from gravitational potential energy to kinetic energy and internal energy.
• How do energy flow diagrams help in understanding energy transfers?

  They visually represent how energy is transferred from one store to another.
• What is the main concept of energy in terms of its stores?

  Energy can be transferred, dissipated, or stored in different ways.
• What does it mean when energy is described as being 'dissipated'?

  Dissipated energy refers to energy spreading out into less useful forms, such as thermal energy.
• Why is dissipated energy often referred to as 'wasted' energy?

  Because it is not transferred to a useful output and is lost to the surroundings.
• What is a common example of energy dissipation in electrical systems?

  Electrical cables warming up is a good example of energy dissipation.
• How does friction contribute to energy dissipation in mechanical systems?

  Friction converts kinetic energy into heat, causing heating of the surfaces.
• How can adding lubricant affect energy dissipation in a mechanical system?

  Adding lubricant reduces friction, leading to less heat being wasted.
• What is an example of an energy-efficient component in electrical systems?

  Using LED light bulbs instead of filament lamps causes less energy to be wasted.
• How does energy dissipation occur in a radio or set of speakers?

  Electrical work is transferred into useful sound waves, while infrared radiation is dissipated as heat energy.
• In a tumble dryer, how is energy transferred and dissipated?

  Electrical work is transferred into useful internal thermal energy, while energy is dissipated by sound waves.
• What are the key concepts related to energy stores and dissipation?

  • Energy can be transferred, dissipated, or stored.
  • Dissipated energy is often considered 'wasted' energy.
  • Friction converts kinetic energy into heat.
  • Lubricants reduce friction and energy waste.
  • Energy-efficient components minimize energy dissipation.
• What are examples of energy dissipation in different systems?

  • In electrical systems: Cables warming up.
  • In mechanical systems: Friction between surfaces.
  • In audio systems: Sound waves produced by speakers.
  • In dryers: Heat used to dry clothes, sound waves dissipated.