Physics AQA Topic 2 (Series and parallel circuits)

4.2.2

What are the two ways that a component can be connected in a circuit

Series and parallel

How does the potential difference across two components vary when connected in series and parallel

Series - total potential difference is shared between each component, parallel - potential difference across each component is the same

If two resistors are connected in parallel, what can be said about their combined total resistance

Their total resistance is less than the smallest of the two individual resistances

If two resistors are connected in series, what can be said about their total resistance

Their total combined resistance is equal to the sum of the two individual resistances (Rtotal = R1 + R2…)

Describe the current in a series circuit

In a series circuit, the current is the same at all positions since the charge only has one path to flow through

Describe the current in a parallel circuit

In a parallel circuit, the current is shared between the different branches so when the charge reaches a junction it splits depending on the resistance of each branch

How should you connect an ammeter in a circuit to measure current

Ammeters should be connected in series with the component they are measuring current through

How should you connect a voltmeter in a circuit to measure potential difference

Voltmeters should be connected in parallel to the component that they are measuring the potential difference of

Why is it advantageous to connect lamps in parallel

If one lamp breaks then the rest will be unaffected and can still receive current (the circuit is still complete)

Explain the design and use of dc series circuits for measurement and testing purposes

Series circuits are designed to build and measure components because the potential difference, current and resistance are easy to change, measure and calculate