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resistor & potentiometer

Resistor is a two terminal passive electrical component that implants electrical resistance.

in electronic circuits, resistors are used to reduce current flow.

ohm's law :


The behavior of an ideal resistor is dictated by the relationship specified by ohm's law.

Ohm's law states that the voltage (V) across a resistor is proportional to the current (I), where the constant of proportionality is the resistance (R).

V=I \cdot R.

resistors in series & parallel :


The total resistance of resistors connected in series is the sum of their individual resistance values.

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R_\mathrm{eq} = R_1 + R_2 + \cdots + R_n.

The total resistance of resistors connected in parallel is the reciprocal of the sum of the reciprocals of the individual resistors.

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\frac{1}{R_\mathrm{eq}} = \frac{1}{R_1} + \frac{1}{R_2} + \cdots + \frac{1}{R_n}.

resistor color code :


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1 potentiometer : 


it is three terminal variable resistor.

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