Electricity - Transfer of energy

Different types of energy include:
-Heat energy
-Sound energy
-Light energy
-Kinetic energy
-Potential energy
-Strain energy
-Chemical energy

Energy is measured in Joules (J)

Useful and Wasted energy

Useful energy is energy that is used up for reasons that you wanted, e.g. Heat energy from a microwave
Wasted energy is energy that is used up for reasons you didn't want e.g. sound energy from boiling water.

Energy efficiency

Energy efficiency is calculated by using the formula: Useful energy/Total energy * 100%

Sankey diagrams

Sankey 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.

	Created by mate spark about 8 years ago

notes on 9I energy