P2.2 energy

• efficiency

  $\frac{usfull}{total}$* 100
• sanky diagrams show

  energy transfers
• renewable

  source wont run out in a lifetime
• non-renewable

  source could run out in a lifetime
• work done is

  force * distance in line with force
• Nm=N*M

  work done =force * distance in line with force
• work done and energy transfer are the same thing
• greater velocity=greater kenetic energy
• greater mass=greater kenetic energy
• kinetic energy= $\frac{1}{2}$*mass *$velocity^2$
• more mass= more GPE
• More gravity =More GPE
• GPE= mass * height * gravity
• $velocity=$$\ \sqrt{\frac{2KE}{m}}$
• $efficiency=$$\frac{usfull\ energy}{total\ energy}\cdot100$
• efficiency is always a percentage
• $power=$$\frac{energy\ }{time}$
• $power=$$\ \frac{work\ done\ }{time}$
• power is

  the amount of energy transferred every second
• coal positive and negative

  infrastructure already in place

  1000s of years worth

  air pollution from greenhouse

  not renewable
• Oil positive and negative

  • stored easily
  • used a lot
  • burning oil=fossil fuels
  • non renewable
• Solar positive and negative

  • renewable
  • inexhaustible
  • lots of maintenance
  • weather dependent
  • expensive
• Wind positive and negative

  • doesn't pollute air
  • low operating cost once up
  • weather dependant
  • requires large areas of impact
• Geothermic positive and negative

  • eco-friendly
  • sustainable, renewable
  • location dependant
  • can trigger earthquakes
• Hydroelectric positive and negative

  • provide flood control
  • doesn't produce waste
  • used for irrigation
  • expensive to set up
  • river may dry up
• Nuclear positive and negative

  • high power density
  • small land footprint
  • radioactive waste
  • high environmental impact