Energy

• Kinetic energy is energy stored in a moving object.
• Gravitational Potential energy is energy stored by an object that is not on the ground in a gravitational field.
• Chemical energy is energy stored in the bonds between atoms.
• Elastic potential energy is energy stored in an object that is squashed or stretched.
• Nuclear store energy is stored in the nuclei of atoms and is released during radioactive decay.
• Internal store energy is the sum of the kinetic energy in an object's particles and the chemical energy in its bonds.
• Electrostatic energy is the energy of attraction or repulsion between electric charges.
• Magnetic energy is the energy of attraction or repulsion between magnets.
• In your body, energy is added to your chemical stores when you eat and is released to keep you warm or to make you move.
• Energy is earned by doing work.
• When a body heats up, the kinetic energy of its particles increases, so does the internal energy.
• Kinetic energy is measured in Joules and is represented by the equation Ek=12mv^2.
• Gravitational potential energy is measured in Joules and is represented by the equation Ep=mgh.
• Elastic potential energy is measured in Joules and is represented by the equation Ee=12ke^2.
• Heating is the process of transferring energy to an object's internal store.
• Waves are a mechanism for transferring energy from one source to another.
• Electrical work is when an electrical current transfers energy from one source to another, such as a battery powering a torch.
• Mechanical work is when a force is applied to another object, for example, weight forcing an object down or you pushing a wheelchair.
• Conservation of energy states that energy cannot be created or destroyed, only transferred, so in a closed system energy cannot change, in an open system it can be lost.
• State the conservation of energy

  Conservation of energy states that energy cannot be created or destroyed, only transferred
• State the equation for Kinetic Energy

  Ek = 1/2mv^2
• State the equation for GPE

  Ep = mgh
• What is energy measured in?

  Joules
• What is mass measured in?

  Kg
• What is gravitational field strength measured in?

  N/kg
• State the equation for EPE

  Ee = 1/2ke^2
• What is Specific Heat Capacity?

  The amount of energy required to raise the temperature of 1kg of a substance by a 1*C.
• State the equation that links energy transferred to Specific Heat Capacity

  Change in thermal energy = mass x SHC x temperature change
• What is SHC measured in?

  J/kg*C
• Define Power

  The rate of energy transfer
• What is power measured in?

  Watts
• State the symbol equation that links power, energy transferred and time

  P = E/t
• State the symbol equation that links power, work done and time

  P = W/t
• What is work done measured in?

  Joules
• What is a powerful machine?

  One which transfers a lot of energy in a short space of time.
• What substances can reduce frictional forces?

  Lubricants
• State the equation for efficiency

  Efficiency = Useful power output / total power input
• What is meant by a non-renewable resource?

  A resource that cannot be replenished or replaced within a human lifespan (will run out and do damage to environment)
• Give three examples of fossil fuels

  Coal, oil and natural gas
• What is meant by a renewable energy resource?

  A resource that will never run out as the energy can be 'renewed' as it is used.