Series circuits
In series circuits, A device in an electric circuit, such as a battery, switch or lamp. are connected one after another in a single loop.
Circuit rules
An Subatomic particle, with a negative charge and a negligible mass relative to protons and neutrons. will pass through every component on its way round the circuit. If one of the bulbs is broken then Moving electric charges, eg electrons moving through a metal wire. will not be able to flow round the circuit. If one bulb goes out, they all go out.
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Current in series
A A circuit where one component follows directly from another, eg three bulbs in a row with no junctions are said to be connected in series. circuit is one loop; all electrons in that loop form one current. An A device used to measure electric current. will measure the same current wherever it is placed in the circuit:
\(I_{1} = I_{2} = I_{3}\)
This is when:
- current (I) is measured in amps (A)
Potential difference in series
The current will transfer The capacity for doing work. from the power supply to the components in the circuit. Since energy has to be conserved, all of the source energy is shared between the components. Since The potential difference (or voltage) of a supply is a measure of the energy given to the charge carriers in a circuit. Units = volts (V). This is the voltage between two points that makes an electric current flow between them. is used to measure changes in energy, the potential difference supplied is equal to the total of the potential differences across all other components:
\(V_{s} = V_{1} + V_{2}\)
This is when:
- Potential difference (V) is measured in volts (v)
Resistance in series
If An electrical component that restricts the flow of electrical charge. Fixed-value resistors do not change their resistance, but with variable resistors it is possible to vary the resistance. are connected in series, the current must flow through both of them, so the resistance is increased. To find the total resistance, the The opposition in an electrical component to the movement of electrical charge through it. Resistance is measured in ohms. are added together:
\(R_{total} = R_{1} + R_{2}\)
This is when:
- resistance (R) is measured in ohms (Ω)