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Parallel circuits

Parallel circuit properties

1) Number of passive components

We first make a parallel circuit including a battery, two lamps and then we add a third lamp connected in parallel:
Parallel circuit with two and three lamps

The brightness of L1 and L2 lamps stays the same despite the addition of a third lamp.

In a parallel circuit, the brightness of a lamp is the same whatever is the number of passive components in this circuit.

2) Burnt out bulb or unscrewed bulb

We make the following parallel circuit in order to observe what happens when unscrewing a lamp:
Parallel circuit with three lamps

Observation: si l'une des lampes est dévissé les autres lampes continuer à briller de la même manière. Nous obtenons le même résultat si la lampe est grillée.

Interprétation: Si une lampe est dévissée les autres continuer à briller car elles sont dans d'autres boucles qui restent fermées.

Conclusion: Dans un circuit parallèle, si la lampe est grillée ou est dévissé les autres composants passifs continuer à fonctionner de façon indépendante.

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