Introduction to Capacitors

Flashcards covering introductory concepts, construction, safety, metric prefixes, and terminology related to capacitors.

What is an electrical conductor?

A material that allows the flow of electric current because free electrons or ions move when a voltage is applied, resulting in very low resistance.

What is an electrical insulator?

A material that does not allow the flow of electric current because it has no free electrons, resulting in very high resistance.

What basic physical components make up a capacitor?

Two conducting surfaces (metal plates) separated by an insulating material called a dielectric.

What are four typical uses for capacitors in electronic circuits?

Time delays, smoothing, filtering, and tuned circuits.

Capacitance is charge stored per volt, and it is measured in farads ($F$ ).

How is capacitance defined, and what is its unit of measurement?

What metric prefix corresponds to a power of ten of $10^{-12}$ in engineering notation?

pico ($p$), representing a value of $\frac{1}{1,000,000,000,000}$.

What metric prefix corresponds to a power of ten of $10^{-9}$ in engineering notation?

nano ($n$), representing a value of $\frac{1}{1,000,000,000}$.

What metric prefix corresponds to a power of ten of $10^{-6}$ in engineering notation?

micro (̑\mu), representing a value of $\frac{1}{1,000,000}$.

What typical capacitance range do electrolytic capacitors provide, and what is their main function in power supplies?

What typical capacitance range do electrolytic capacitors provide, and what is their main function in power supplies?

What potential hazard occurs if an electrolytic capacitor is connected incorrectly or subjected to excessive voltage?

It can explode if connected the wrong way or if its maximum working voltage is exceeded.

Why is it important to safely discharge high-capacitance or high-voltage capacitors before working on them?

They store electrical charge that must be safely discharged to avoid electrical shock or component damage.

How are practical rolled capacitors constructed as shown in the diagram?

By interleaving metal foil plates with two dielectric layers and rolling them up, staggering the plates to make electrical connections at each end.

In the multi-layered capacitor cross-section shown, what dielectric material is used between the inner nickel electrodes?

$\text{CaZrO}_3$ (Calcium zirconate).

In an aluminum electrolytic capacitor structure, what covers the etched anode aluminum foil layer?

Aluminum oxide.