- English
- Deutsch
- Português
- Español
- Electrical engineering
- Voltage Current Resistance
- Star Delta Transformation
- Practical Voltage and Current Sources, equivalent circuit diagram
- Capacitor to DC voltage
- Inductors in DC Circuits
- Alternating current
- AC Inductive Circuits
- Three-phase Current
- Transformer
- Complex numbers
- Locus Diagram in AC circuits
- Videos electrical engineering
- Index electrical engineering

**Home ⇒ Overview Courses ⇒ Electrical engineering ⇒ Series connection of Resistors**

**Series c****onne****cti****on ****of Resistors**

The following applies in general for series connection:

**The same current flows through each part of a series circuit.**

There is only one current

**Voltage applied to a series circuit is equal to the sum of the individual voltage drops.**

**V _{t} = V_{1} + V_{2} + … + V_{n} ** (1)

The **total resistance** of a series circuit **is equal** to the **sum of individual resistances**.

**R _{t } = R_{1} + R_{2} + … + R_{n}** (2)

We proof this:

Eq. (1) divided by I:

__V___{t} = __V___{1} + __V___{2} + … + __V___{n}

.I I I I

=> According to the Law of Ohm we get equation (2).

**Work order:** Calculate the necessary series resistor!

First calculate the necessary current for the lamp:

P_{L} = V_{L} * I => I = P_{L} / V_{L} = 2W / 12V = 0,167 A

Then you can apply the Law of Ohm. Note:

V_{RV} = V_{Bat} - V_{L} = 24 V - 12 V = 12 V

R_{V} = V_{RV} = __12 V__ = 71,86 Ω

. I 0,167 A