Phys: Energy

• What does the prefix 'nano' represent in terms of a factor?

  It represents $10^{-9}$
• What are the different types of energy stores mentioned?

  Thermal, kinetic, elastic, chemical, and magnetic
• What is the significance of stored electric charge?

  It is important for determining energy in objects
• What is the unit for energy?

  Joules (J)
• What does the prefix 'kilo' mean?

  It means $10^{3}$
• What does the prefix 'micro' mean?

  It means $10^{-6}$
• What store of energy is associated with moving objects?

  Kinetic energy
• What stores of energy are associated with fuels and food?

  Chemical energy
• What energy transfer uses waves?

  Radiation
• What energy transfer uses forces?

  Mechanical work
• What store of energy does waste energy usually transfer into?

  Thermal energy
• What is the equation for calculating gravitational potential energy (GPE)?

  GPE = mass x gravitational field strength x height
• What is the value of gravitational field strength on Earth?

  
  

  9.8N/kg
• What is the efficiency equation?

  Efficiency = useful output energy / total input energy
• What are the differences between renewable and non-renewable energy sources?

  Non-Renewable:

  • Nuclear: no CO2
  • Coal: radioactive waste
  • Oil
  • Natural gas: will run out, release CO2

  
  

  Renewable:

  • Biomass
  • Hydrogen (transport)
  • Hydroelectric (dams)
  • Wind
  • Solar
  • Tidal
  • Wave Can be replenished
• What are the advantages and disadvantages of renewable energy sources?

  Advantages:

  • Can be replenished
  • Lower CO2 emissions

  
  

  Disadvantages:

  • Expensive
  • Land use issues
  • Weather dependent
  • Noise pollution
• What is the formula for calculating power when given work and time?

  Power = Work / Time
• How does the energy transfer differ between mechanical work and radiation?

  Mechanical work uses forces, while radiation uses waves
• What is the unit of power?

  Watts (W)
• What is the relationship between power, work, and time?

  Power is the rate of doing work over time
• What is the significance of energy transfer in physical processes?

  Energy transfer is crucial for performing work and changing states
• How do renewable energy sources impact the environment compared to non-renewable sources?

  Renewable sources generally have lower CO2 emissions and less environmental impact
• What is the relationship between work, energy, and power?

  Work is the transfer of energy, and power is the rate of doing work
• How does the efficiency of a kettle relate to its energy input and output?

  Efficiency measures how much useful output energy is produced from total input energy