Energy – forces doing work GapFill

A system stores energy in a variety of different ways. When the system changes, this energy is transferred between stores. Energy can be transferred by heating or  raising efficiencyreducing powerpotentialsdoing work. Energy is measured in  wattsampsjoulesnewtons.
The energy stored by an object due to its motion is called  elastic potential energygravitational potential energykinetic energythermal energy.
The energy stored by an object due to its having been deformed is called  kinetic energythermal energyelastic potential energygravitational potential energy.
The energy stored by an object due to its position in a gravitational field is called  potential energyelastic potential energygravitational potential energykinetic energy.
The energy stored by an object due to its temperature is called  thermal energygravitational potential energypotential energychemical energy. The energy required to raise the temperature of a 1 kg object by 1 °C is called its  specific heat capacityheat coefficientspecific latent heatthermal conductivity.
The rate at which an energy transfer happens, given by energy transferred ÷ time, is called the  currentefficiencyvoltagepower of the transfer, and this is measured in  ampswattsnewtonsjoules.

Whenever a force changes a system, work is done. The work done by a force is equivalent to  the time taken bythe energy transferred bythe power ofthe size of the force.

Mains electricity is delivered by the national grid, which connects power stations to homes and businesses. At power stations, the potential difference of the electricity is increased using  step-down transformersramping solenoidsstep-up transformerssliding solenoids for transmission, and in homes the potential difference is decreased using  ramping solenoidsstep-up transformerssliding solenoidsstep-down transformers for use by appliances.

If a transformer was 100 % efficient, then  Vp × Ip = Vs ÷ IsVp ÷ Ip = Vs × IsVp ÷ Ip = Vs ÷ IsVp × Ip = Vs × Is.