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How is current shared in a parallel circuit?

Just a quick question.

I know current is shared in a parallel circuit between components but what determines how much each component gets?
Original post by BTAnonymous
Just a quick question.

I know current is shared in a parallel circuit between components but what determines how much each component gets?


Something called resistance.

Resistance can be calculated using R = V / I , where R is resistance in Ohms, V is potential difference in Volts and I is the current in Amps.

If the resistance across a component or wire is high, then not a lot of current will pass through it, and vice versa.
Original post by leafcannon
Something called resistance.

Resistance can be calculated using R = V / I , where R is resistance in Ohms, V is potential difference in Volts and I is the current in Amps.

If the resistance across a component or wire is high, then not a lot of current will pass through it, and vice versa.


So lets say all components have the same resistance in a parallel circuit.

If branch 1 only has 1 component but branch 2 has 2 components, then more current will pass through branch 1 than branch 2?
Original post by BTAnonymous
So lets say all components have the same resistance in a parallel circuit.

If branch 1 only has 1 component but branch 2 has 2 components, then more current will pass through branch 1 than branch 2?

yep
It's to do with resistance. Say that on the first branch of the parallel circuit there is a resistance of 2 ohms, and on the second branch there is a resistance of 4 ohms. The current passing through the first branch will be higher than the current passing through the second branch. This is because of the relationship between current and resistance, they are inversely proportional so current will increase when the resistance decreases. Makes sense? :smile:

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