This leads us to another principle of series circuits: The total resistance of a circuit is equal to the sum of all the individual resistances. How do you determine the total resistance value of the series circuit? However, we don’t know the total resistance of the circuit, even though we know all the resistance values of all the resistors of a circuit. We know the voltage (V1) of the circuit is 9V. Unfortunately, we don’t know the current that flows in the whole circuit in our previous example.ĭo you remember the ohm’s law formula we covered earlier?īy rearranging the elements correctly from the ohm’s law pyramid, we can calculate the current using the voltage of the series circuit divided by the resistance.Ĭurrent = Voltage / Resistance Formula to Calculate the Current using Ohm’s Law How do you calculate the current in a series circuit? If we apply this concept to the previous circuit, that means the current will be the same after resistance R1 and resistance R2. Series circuits have one principle which we will need to take into account when calculating the voltage drop across resistors: the current is the same through all of the components of the circuit. Ohm’s law is best described by using a pyramid displaying the relationship between these three values.

Ohm’s law is a formula commonly taught to students of electronics and it helps to calculate the relationship between the voltage, current, and resistance of a circuit. If you haven’t heard of Ohm’s law before, we are going to take a quick stop to understand it. When talking about the voltage drop across a resistor, we are referring to the voltage across a resistor, or the voltage once the current flow has gone through a resistor. The first circuit with only one resistor, and the second circuit with two resistors. In the image above, you will see two circuits. Understanding Voltage Drop Across a Resistor Let’s take the following circuits in the image below to help provide more clarity. Talking about calculating the voltage drop across a resistor wouldn’t make sense if we don’t understand what is the voltage drop across a resistor.

Conclusion What is the voltage drop across a resistor?.

Why do I need to drop the voltage in a circuit?.

How do you calculate the current in a series circuit?.

Calculate Voltage Drop Across Resistors Based on the Circuit Type.

What is the voltage drop across a resistor?.

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