1. Parallel Circuits Definition: Parallel Circuit
A circuit that provides more than one current path between any two points is said to be a parallel circuit.
EGR 101

2. Example
Circuit (a) provides two current paths between points (nodes) A and B.
Circuit (b) provides three current paths between Ground and the + terminal of the battery.
The PC Board circuit provides four current paths between the input terminals.
EGR 101

3. Currents in the Parallel Branches Kirchhoff’s Current LawIT
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4. KCL
The voltages across the parallel components are equal!
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5. Equivalent Resistance
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6. Special Case for 2 Resistors
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7. Common Mistake
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8. Equal Resistors in Parallel
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9. Total (Equivalent) Resistance Is Always Lower Than Any Individual Resistor
Consider the following circuit.
By the numbers, the total (Equivalent) Resistance is equal to 10V/10mA, or 1 kΩ.
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10. What About the Power?
The power delivered by the source is equal to the sum of the individual powers dissipated in the resistors.
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11. Summary
EGR 101