Energy

• What is conduction in terms of energy transfer?

  Conduction is the transfer of energy through vibrating particles.
• How does lubrication affect friction?

  Lubrication reduces frictional energy transfer.
• What is efficiency in energy transfer?

  Efficiency is the proportion of input energy transfer that is usefully transferred.
• What does insulation do to energy transfer?

  Insulation reduces the rate of energy transfer.
• What are non-renewable energy resources?

  • Resources that will run out
  • Examples: Gas, Nuclear fuel
  • Reliable but can damage the environment
• What are renewable energy resources?

  • Resources that can be replenished
  • Examples: Sun, Wind, Hydroelectricity, Bio-fuel, Water waves
  • Some are unreliable
• What are the advantages of wind power?

  Wind power has no pollution, no fuel costs, and no permanent damage to the landscape.
• What are the disadvantages of wind power?

  Wind power can spoil the view, is very noisy, and has high initial costs.
• What are the eight energy stores?

  • Kinetic
  • Chemical
  • Magnetic
  • Gravitational Potential
  • Nuclear
  • Elastic Potential
  • Electrostatic
  • Thermal
• What is the formula for gravitational potential energy?


  Gravitational potential energy is given by $GPE =$$mgh$.
• What is the formula for elastic potential energy?

  Elastic potential energy is given by $PE =$$\frac{1}{2}kx^2$.
• What does the term "power" refer to in energy transfer?

  Power is the rate of energy transfer.
• What is the formula for power in terms of energy transfer?

  Power is given by $P =$$\frac{E}{t}$, where $E$ is energy and $t$ is time.
• What does the law of conservation of energy state?

  Energy cannot be created or destroyed, only transferred, stored, or dissipated.
• How does energy transfer occur in different forms?

  Energy can be transferred mechanically, electrically, by heating, or by radiation.
• If a substance's temperature changes by $\Delta T =$$48°C$, what is the formula to calculate the energy needed to raise its temperature?


  The energy needed is given by $Q =$$mc\Delta T$.
• What is the specific heat capacity?

  Specific heat capacity is the amount of energy needed to raise the temperature of 1 kg of a substance by 1°C.
• What does the term "input energy transfer" refer to?

  Input energy transfer refers to the total energy supplied to a system.
• How does energy efficiency relate to useful output energy transfer?

  Efficiency is the ratio of useful output energy transfer to total input energy transfer.
• What does insulation do to energy transfer?

  Reduces the rate of energy transfer.