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Parallel Cirque. In these circuits, the load devices are connected on different branches

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of the wire. There are several possible paths for the electric current to flow through.

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The electric current is split across all the possible paths and more current will circulate

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through the branch that offers the least resistance. The current intensity that flows

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through each load device is different. Even if one of the load devices stops working,

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the rest continue to work because the electric current takes another path,

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the circuit is closed by another path. The energy supplied by the cell reaches each branch of the

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circuit directly. Therefore, all the lamps shine with the same brightness as a single lamp located

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on a single branch. However, the cell will run down sooner. To simplify things, we will solve

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a circuit formed by three resistors connected in parallel to a cell. The equivalent resistance of

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a circuit with parallel resistors is calculated using this formula. Since this circuit is

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equivalent to the last one, the current flowing through the two circuits will be the same.

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We apply Ohm's law to calculate the current flowing through the equivalent resistance.

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Since the resistors are in parallel, the potential drop or voltage is the same in them all and it is

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equal to the cell voltage. Vt equals V1 equals V2 equals V3. By contrast, the total intensity

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through the circuit is divided across all the resistors. We can calculate this with Ohm's law.

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The total intensity is divided through the resistors in parallel, so the addition of the

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intensities should give the total intensity. The inverse of the equivalent resistance is equal to

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the sum of the inverses of all resistances in the circuit. The current of the equivalent circuit is

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equal to the sum of the currents flowing across each of the resistors. The total voltage delivered

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by the power source is the same as the potential drops across each of the resistors. Example of a

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parallel circuit. From the parallel circuit shown in the figure, calculate the current flowing

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through each resistor and the potential drop across each one. First, we use the above formula

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to calculate the equivalent resistance. You need to use the calculator. Remember that the formula

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gives you the inverse of the equivalent resistance, so you need to calculate the inverse.

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Again use the calculator. We use Ohm's law to calculate the total current.

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The potential drop in each branch is equal to the voltage supplied by the cell.

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To calculate the current flowing through each resistor,

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we apply Ohm's law using the voltage values that we just calculated.

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So divide the cell voltage between each of the values of the resistors.

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We can check that we have done the exercise correctly by adding up the current of all the

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resistors. The result should be equal to the total current.

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you