WEBVTT

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Here is the problem: Resistors of 20, 30 Ω are connected in parallel across 6 V. Find the equivalent resistance and total current.

2
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Resistors in parallel share the same voltage; their conductances (1/R) add.

3
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Parallel: reciprocals add.

4
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Total current from Ohm prime s law.

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Current in each branch (same voltage). The branch currents add up to the total current.

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Power delivered.

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So the answer is R T equals 12 Ω; I equals 0.5 A, P equals 3 W.

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The equivalent resistance of a parallel network is always smaller than its smallest resistor; two equal resistors in parallel give half of one.

9
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R T less than or equal to every individual resistor, which checks out.