Topic 3 - conservation of energy

• What is the formula for change in gravitational potential energy?

  $ΔGPE =$$m *$$g *$$Δh$
• What is the formula for kinetic energy?

  $KE =$$1/2 *$$m *$$v^2$
• What type of diagram is this?

  Sankey diagram.

  
• what is meant by the conservation of energy?

  Energy cannot be created or destroyed. It can only be stored or transferred.
• Analyse how energy is transferred in a ball rolling up a slope:

  The ball does work against the gravitational force, so energy is transferred mechanically from the kinetic energy store of the ball to its gravitational potential energy store.
• Analyse how energy is transferred from a bat hitting another ball:

  The bat has energy in its kinetic energy store. Some of this is transferred mechanically to the ball's kinetic energy store. Some energy is also transferred mechanically to the thermal energy stores of the bat and the ball (and to the surroundings by heating). The rest is carried away by sound.
• There is no change in total energy during its transfer.
• Mechanical processes can be wasteful as they create energy from friction.
• In a light, energy could be wasted as heat.
• You can reduce energy transfer of mechanical devices through lubrication, insulation, and air sealing as it reduces friciton.
• The thicker the walls of a building, the slower its rate of cooling.
• What is the formula for efficiency?

  Efficiency = Useful energy transferred by device / Total energy transferred by device.

  
• What are the advantages and disadvantages of using fossil fuels?

  Advantages: Energy-dense, widely available, and established infrastructure. Disadvantages: Environmental pollution, finite resource, and contribution to climate change.
• What are the advantages and disadvantages of using nuclear fuels?

  Advantages: High energy output, low greenhouse gas emissions. Disadvantages: Radioactive waste, potential for accidents.
• What are the advantages and disadvantages of using bio fuels?

  Advantages: Renewable, reduces greenhouse gas emissions, supports rural economies. Disadvantages: Land and water use, potential for deforestation, competition with food production.
• What are the advantages and disadvantages of hydroelectricity?

  Advantages: Renewable, clean, and reliable source of energy. Disadvantages: Environmental impact, limited availability of suitable locations.
• What are the advantages and disadvantages of using Tidal energy?

  Advantage: Eco-friendly

  Disadvantage: expensive
• What are the advantages and disadvantages of using Solar energy?

  Advantages: Renewable, clean, reduces greenhouse gas emissions, low operating costs. Disadvantages: High initial costs, intermittent availability, requires large land area, dependent on weather conditions.
• Explain patterns and trends in the use of energy resources:

  we are still reliant on fossil fuels however we are slowly transitioning to clean energy as our sources of energy are becoming renewable and safe for the environment.