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Passive components are those that do not require a power source to operate, unlike active components which require a power source to run. Passive components include the resistors, capacitors and inductors. Resistors are cheap and simple to understand but they do not provide a perfect voltage drop. Capacitors store energy in an electric field but require more space than resistors and are not as simple to calculate. Inductors will have a coil of wire which is used by alternating currents to create a magnetic field that opposes changes in current or voltage. They work where it is easier for them than for capacitors or resistors so they are commonly found in power supplies, radios and televisions because these devices put out alternating signals of various frequencies.

The three basic passive electronic components


Resistors are electrical components similar to a tape measure. They use a metal strip that has been marked in steps which have been designated by their value of resistance. Resistors can be used across switches and light switches to protect them from excess voltage or current as well as to reduce overall power consumption. It is important to note that while they can be placed across capacitors, they are not the same thing, by definition. The voltage drop across a capacitor depends on the capacitance of it while the voltage drop across a resistor will stay constant regardless of how much electricity flows through it.


Capacitors are electronic components similar to an automobile’s battery but not quite as big. It uses a pair of metal plates with one being positively charged and the other being negatively charged. The plates are separated by an insulator, which is a non-conducting material that offers no resistance to the flow of electricity.

Capacitors have high capacitance and low internal resistance. They can be used to filter out high frequencies from an alternating current or voltage in an electric circuit.

The three basic passive electronic components 2


Inductors are electronic components similar to a coil of wire, they can be thought of as transformers without the iron core. When alternating current is run through a coil it creates magnetic field around it that opposes changes in voltage or current. The magnetic field produced by the coil is contained between the two wire windings and must be connected to at least one terminal of the device in order for it to work.

Inductors are used in electronic circuits where alternating current or voltage needs to be converted from one form of energy to another. These are mostly found in audio and radio equipment as well as power supplies. They can also be found in mechanical systems like motors and generators.


All three of these devices can be used in series or parallel depending on the device’s voltage drop tolerance and how much total energy is required. They can be found in electronic circuits, generators, power supplies, radios, televisions and even mechanical systems like motors and generators. The inherent limitations of each of these devices as well as the uses they are best suited for makes them an important part of understanding how electronics work with the goal of coming up with better and more efficient designs.