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Parallel Circuit Formula:
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The equivalent resistance of a parallel circuit is the single resistance value that can replace multiple resistors connected in parallel, maintaining the same total current flow in the circuit. It is always less than the smallest individual resistor in the parallel combination.
The calculator uses the parallel resistance formula:
Where:
Explanation: The reciprocal of the equivalent resistance equals the sum of the reciprocals of all individual resistances in the parallel circuit.
Details: Calculating equivalent resistance is essential for circuit analysis, design, and troubleshooting in electrical engineering and electronics. It helps determine total current flow, power consumption, and voltage distribution in parallel circuits.
Tips: Enter resistor values separated by commas (e.g., "10, 20, 30"). All values must be positive numbers. The calculator will compute the equivalent parallel resistance.
Q1: Why is equivalent resistance less in parallel circuits?
A: Adding resistors in parallel provides additional paths for current flow, effectively reducing the overall resistance in the circuit.
Q2: What happens if one resistor fails in a parallel circuit?
A: In a parallel circuit, if one resistor fails (opens), current can still flow through other paths, though the total resistance and current distribution will change.
Q3: How do you calculate total current in a parallel circuit?
A: Total current equals the source voltage divided by the equivalent resistance (I = V/Req), following Ohm's Law.
Q4: Can the equivalent resistance be zero?
A: No, equivalent resistance approaches zero only when an infinite number of zero-resistance paths are added, which is not physically possible with real resistors.
Q5: What's the difference between series and parallel resistance calculation?
A: In series circuits, resistances add directly (Req = R1 + R2 + ...). In parallel circuits, reciprocals of resistances add (1/Req = 1/R1 + 1/R2 + ...).