P1- Energy

• What are the energy stores?

  Chemical, Kinetic, Elastic, Potential, Magnetic, Gravitational, Internal
• What is the formula for kinetic energy?


  $EK =$$\frac{1}{2} mv^2$
• How is gravitational potential energy calculated?


  Gravitational potential energy is calculated using the formula $GPE =$$mgh$
• What does the variable 'm' represent in the gravitational potential energy formula?


  'm' represents mass in kilograms
• What does the variable 'g' represent in the gravitational potential energy formula?


  'g' represents the gravitational field strength
• What is the formula for elastic potential energy?


  $EP =$$\frac{1}{2} k x^2$
• What does 'k' represent in the elastic potential energy formula?


  'k' represents the spring constant
• What is the formula for work done?


  $W =$$F \times d$
• How is power calculated?


  Power is calculated using the formula $P =$$\frac{W}{t}$
• What is the formula for energy in terms of power and time?


  $E =$$P \times t$
• What is the principle of conservation of energy?


  • Energy cannot be created or destroyed
  • Energy can only be transferred
• How can efficiency be calculated?

  Efficiency is calculated using the formula $\text{Efficiency} =$$\frac{\text{Total energy output}}{\text{Total energy input}} \times 100$
• What are the advantages and disadvantages of fossil fuels?


  Advantages:

  • Reliable
  • High energy output

  
  

  Disadvantages:

  • Non-renewable
  • Inefficient
• What are the advantages and disadvantages of geothermal energy?


  Advantages:

  • Renewable
  • Low emissions

  
  

  Disadvantages:

  • Location specific
  • Limited availability
• What are the advantages and disadvantages of wind power?


  Advantages:

  • Renewable
  • Low cost

  
  

  Disadvantages:

  • Unreliable
  • Noise pollution
• What are the advantages and disadvantages of hydroelectric power?


  Advantages:

  • Renewable
  • Predictable energy source

  
  

  Disadvantages:

  • Can disrupt ecosystems
  • Limited suitable locations
• What are the advantages and disadvantages of nuclear energy?


  Advantages:

  • No greenhouse gas emissions
  • Reliable energy source

  
  

  Disadvantages:

  • Radioactive waste
  • Difficult disposal
• What are the advantages and disadvantages of solar energy?


  Advantages:

  • Renewable
  • No emissions

  
  

  Disadvantages:

  • Unreliable
  • High initial costs
• What are the uses of renewable resources?


  • Heating buildings with geothermal pumps
  • Solar water heaters
• What are the uses of non-renewable resources?


  • Natural gas for heating homes
  • Coal for burning in fireplaces
• What are the environmental impacts of using fossil fuels?


  • Contributes to pollution
  • Damages the environment
• What are the environmental impacts of using biofuels?


  • Less harmful to the environment
  • Some vehicles powered by biofuel
• What are the environmental impacts of using petrol and diesel vehicles?


  • Contributes to pollution
  • Uses fuel from oil
• What are the examples of renewable energy resources?

  • Solar
  • Wind
  • Water waves
  • Hydro-electricity
  • Biofuel
  • Tidal
  • Geothermal
• What are the examples of non-renewable energy resources?

  • Fossil fuels
  • Nuclear
• What is a system in physics?

  An object or group of objects
• How does energy storage change in a system?

  It changes when the system changes
• What happens to kinetic energy when a ball hits a wall?

  • Kinetic energy is transferred as sound
  • The system is the moving ball
• What occurs to a vehicle's kinetic energy when it slows down?

  • Kinetic energy transfers to thermal energy
  • This occurs due to friction between wheels and brakes
• What is the formula for kinetic energy?

  $E_k =$$\frac{1}{2}mv^2$
• What do the variables in the kinetic energy formula represent?

  m is mass, v is speed
• What is elastic potential energy?

  Energy stored in a stretched spring
• What is the formula for elastic potential energy?

  $E_e =$$\frac{1}{2}ke^2$
• What do the variables in the elastic potential energy formula represent?

  k is spring constant, e is extension
• What is gravitational potential energy?

  Energy due to an object's height
• What is the formula for gravitational potential energy?

  $E_p =$$mgh$
• What do the variables in the gravitational potential energy formula represent?

  m is mass, h is height, g is gravitational strength
• What is specific heat capacity?

  Energy to raise 1kg by 1°C
• What is the formula for calculating thermal energy change?

  $E =$$mc\Delta T$
• What do the variables in the thermal energy change formula represent?

  m is mass, c is specific heat capacity