VOLTAGE

=Voltage= Voltage (or potential difference) is the energy gained or lost by each coulomb of charge as they flow between two points in the circuit. Voltage is measured in '''Volts (V)'''. A battery / power source provides the energy (by setting up an electric field) to push the electrons through the circuit. Electrons will gain energy as they are "pushed" from different points in the circuit. This energy is then lost when the electrons flow through circuit components such as a light bulb. [image:http://i.imgur.com/CMHkIAi.png] E.g. If a battery labelled 5V, it means that a single unit of charge will gain 5J of energy when traveling between its terminals. E.g. If the Voltage measured across a lamp is 3V, it means that each unit of charge is losing 3J of energy which is being converted into heat and light as it travels across the lamp. A voltmeter has to be attached onto a circuit (parallel) to measure the gain or drop in energy across a circuit component. The battery / power source provides the electrons with energy to move through the circuit. The electrons loose this energy as they pass through circuit components such as the bulb shown [image:http://i.imgur.com/XeVNdqA.gif] When cells are added end-to-end (in series) their voltage can be added together. However if one cell is inserted the wrong way around its voltage is actually subtracted. E.g. if the following cells are all 1.5V [image:http://i.imgur.com/du1zLUf.png]