Energy

Electricity - Transfer of energyDifferent types of energy include:-Heat energy-Sound energy-Light energy-Kinetic energy-Potential energy-Strain energy-Chemical energyEnergy is measured in Joules (J)Useful and Wasted energyUseful energy is energy that is used up for reasons that you wanted, e.g. Heat energy from a microwaveWasted energy is energy that is used up for reasons you didn't want e.g. sound energy from boiling water.Energy efficiencyEnergy efficiency is calculated by using the formula: Useful energy/Total energy * 100%Sankey diagramsSankey diagrams are used to show how much energy is useful or wasted, and what type of energy is used up.Electricity-The size of the electric current is measured in amps (A)-It is measured using an ammeter-The amount of energy the cell gives to the current is called the voltage, and is measured in volts (V)-It is measured using a voltmeter.-Voltmeters are connected parallel to a cell or component in a circuit.-When you add up all the voltages across the components the total is the same as the voltage across the cell.-You can increase the voltage in a circuit by using more cells or using cells with a stronger voltage.-The stronger the voltage, the stronger the current.-Resistors reduce the size of the current in a circuit.