How to Analyze Resistive Circuits Using Ohm's Law

Step-by-Step Guide

1. 1

   Step 1: Decide if your circuit is wired in series or parallel.

   When a circuit is wired in series, there is only one path for current to flow.
   
   When a circuit is wired in parallel, there are multiple paths that the current can move through simultaneously.
   
   These two types of circuits behave very differently, and it is important to recognize one from the other., Voltage can be calculated for resistive circuits by using Ohm’s Law.
   
   In order to do this calculation, you will need to know values for the current and resistance of the circuit.
   
   By multiplying these values together, you will find the voltage of the circuit.Take, as an example, a circuit that has a current of 3 Amperes (I = 3A) and a resistance of 2 Ohms (R = 2 ohms).
   
   The voltage (V) for this circuit would be found by using the following equation:
   V=I×R{\displaystyle V=I\times R} V=3 A×2 ohms{\displaystyle V=3{\rm {{\ A}\times 2{\rm {\ ohms}}}}} V=6 V{\displaystyle V=6{\rm {\ V}}} , Using Ohm’s Law, current can be calculated for a resistive circuit.
   
   To do this calculation, you will need to know the values for the resistance and voltage of the circuit.
   
   Divide the voltage by the resistance to obtain the current of the circuit.Take, as an example, a circuit that has a voltage of 6 volts (V = 6V) and a resistance of 2 Ohms (R = 2ohms).
   
   The current (I) for this circuit would be found by using the following equation:
   V=I×R{\displaystyle V=I\times R} V/I=R{\displaystyle V/I=R} 1/I=R/V{\displaystyle 1/I=R/V} I=V/R{\displaystyle I=V/R} I=(6 V)/(2 ohms){\displaystyle I=(6{\rm {{\ V})/(2{\rm {{\ ohms})}}}}} I=3 A{\displaystyle I=3{\rm {\ A}}} , Ohm’s Law will allow you to find the resistance of a resistive circuit.
   
   You must know the values of voltage and current of the circuit to calculate the resistance.
   
   When these values are known, you can find the resistance by dividing the voltage of the circuit by the current.Take, as an example, a circuit that has a voltage of 6 volts (V = 6V) and a resistance of 2 Ohms (R = 2ohms).
   
   The current (I) for this circuit would be found by using the following equation:
   V=I×R{\displaystyle V=I\times R} V/R=I{\displaystyle V/R=I} 1/R=I/V{\displaystyle 1/R=I/V} R=V/I{\displaystyle R=V/I} R=(6 V)/(3 A){\displaystyle R=(6{\rm {{\ V})/(3{\rm {{\ A})}}}}} R=2 ohms{\displaystyle R=2{\rm {\ ohms}}} , Make a table with three rows and a column for each resistor in the circuit, plus one for the overall circuit.
   
   For example, if you have a circuit with three resistors, you would make a table that is three rows by four columns.
   
   The first row will correspond to voltage across each resistor, the second will correspond to current through each resistor, and the third will correspond to the resistance of each resistor.For circuits in parallel:
   The voltage across all resistors is the same and is equal to the voltage of the total circuit.
   
   This means all values in Row 1 will be the same.
   
   The current of the total circuit is the sum of the current through all resistors.
   
   This means that the final column in Row 2 will be equal to the sum of all other columns in Row
   2.
   
   The total resistance diminishes as resistors are added.
   
   For a circuit with “n” resistors, the last column in Row 3 will be found with the equation: 1 / ((1/R1) + (1/R2) … + (1/Rn-1) + (1/Rn)).
2. 2

   Step 2: Find the voltage of the circuit.

3. 3

   Step 3: Solve for the current of the circuit.

4. 4

   Step 4: Calculate the resistance of the circuit.

5. 5

   Step 5: Understand the “Table Method.” The table method is a great way to calculate the resistance of different resistors in the same circuit.

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