Physics T1: Energy

• what are the energy stores?

  Chemical,

  thermal,

  kinetic,

  gravitational,

  elastic,

  nuclear,

  electromagnetic,
• equation for Kinetic energy

  E= 1/2 mv^2
• Equation for CHANGE in Gravitational potential energy

  E= mgh g= gravitational field strength
• Elastic potential energy equation

  E= 1/2ke^2 k= spring constant and e= extention
• Thermal energy equation

  Change in thermal energy=m*specific heat capacity*temp change
• Specific heat capacity practical

  Measure mass of metal block or water in beaker using balance

  Place heater in metal block

  measure initial temperature

  turn heater on , start timer and measure pd and current

  After set time measure final temp and calculate change in temperature

  Calculate power

  calculate energy

  calculate SHC by rearranging equation
• Power equation

  P=E/t
• Equation for efficiency

  Efficacy = Useful / Total x 100

  Efficiency = input / output x 100
• Non renewable source examples

  fossil fuels

  nuclear
• renewable energy source example

  wind power

  hydroelectric

  solar power

  biofuels