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Association of resistors and power sources

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Association of resistors

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Circuits can have various electrical components,

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but when we are learning the basics we generally only start with cells and resistors.

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The way that we put these resistors together is called the association of resistors.

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This gives us three types of basic circuits.

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Series Cricket

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Parallel Circuit

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Series Parallel Combination Circuit

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To perform the electrical calculations of a circuit with several resistors,

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we calculate the value of a single resistor,

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equivalent to the association of the resistors in the circuit.

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The circuit formed with the equivalent resistances is called an equivalent circuit.

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We can obtain three things from this circuit.

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The currents flowing through the circuit.

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The potential drops across the components.

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The dissipated power and the delivered power.

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Series Circuits

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The equivalent resistance is equal to the sum of all resistances in the circuit.

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The current flowing through all of the resistors in the circuit is the same

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and is equal to the current of the equivalent circuit.

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The total voltage delivered by the power source

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is the sum of the potential drops across each of the resistors.

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It is a voltage divider.

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The power delivered by the power source

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is equal to the sum of the powers consumed by each resistor.

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Parallel Circuits

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The inverse of the equivalent resistance

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is equal to the sum of the inverses of all resistances in the circuit.

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The current of the equivalent circuit

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is equal to the sum of the currents flowing across each of the resistors.

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It is a current divider.

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The total voltage delivered by the power source

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is the same as the potential drops across each of the resistors.

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The power delivered by the power source

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is equal to the sum of the power consumed by each resistor.

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Series-Parallel Combination Circuit

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To solve a series-parallel combination circuit,

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we need to find out which resistors are in series and which are in parallel.

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Then we can apply the equations for each case.

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Energy Balance

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The ratio of delivered power to power consumed.

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The energy balance of the circuit is

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Power delivered by the power source equals power consumed by the resistors.