Components share the same voltage and currents add.
In parallel, all branches share one voltage and currents add: 1/R=Σ1/Rᵢ. Total resistance is smaller than the smallest branch. Household wiring is parallel so each appliance gets full voltage.
100 Ω in parallel with 100 Ω gives 50 Ω.
Parallel circuits let each branch work independently at the same voltage, which is how household outlets and car electrical systems are wired.
Components share the same voltage and currents add.
Parallel circuits let each branch work independently at the same voltage, which is how household outlets and car electrical systems are wired.
Its reciprocal is the sum of the reciprocals, so the total is always less than the smallest individual resistance.
All branches connect to the same two nodes, so they share the same voltage, and each takes the current its own resistance allows.
Typical applications include wiring several appliances to one wall outlet, connecting multiple LEDs that must each receive the full supply voltage and adding a second battery to increase capacity in parallel.
Study "Series circuits" first (topic 8 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Two resistors: R=R₁R₂/(R₁+R₂). Branch failure does not stop others. Current divides inversely to resistance.
100 Ω in parallel with 100 Ω gives 50 Ω.
The next topic is "Kirchhoff's current law", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 9 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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