kapasitassit

Kapasitassit is a term that may appear in Finnish electronics discussion, though the standard Finnish nouns are kapasitassi (singular) and kapasitassit (plural) when referring to capacitance, and kondensaattori for the device known as a capacitor. In practice, kapasitassit is often used informally to mean either the electrical property (capacitance) or, less formally, the capacitive components themselves. This article focuses on the concept of capacitance and on capacitors as components, clarifying both usages.

Capacitance, the kapasitassi, is the ability of a passive two-terminal element or circuit to store electric energy in an electric field. It is measured in farads (F) and denoted by the letter C in equations. A larger kapasitassi means more energy storage per volt of potential difference. The energy stored in a capacitor is E = 1/2 C V^2. In circuits, capacitors present a reactance Xc = 1/(2πfC) to alternating current, and a time constant τ = RC describes how quickly a circuit charges or discharges.

Capacitors come in many types and form factors. Common families include ceramic, film, electrolytic (including tantalum), and mica capacitors, as well as supercapacitors for higher energy storage. They may be fixed or adjustable and rated by capacitance value, voltage rating, tolerance, and temperature coefficient. Non-ideal characteristics such as equivalent series resistance (ESR), equivalent series inductance (ESL), leakage current, and dielectric absorption affect performance, especially at high frequencies or large voltages.

Applications span decoupling and filtering in power supplies, signal coupling and timing in analog circuits, and energy storage in power electronics. Capacitance values range from picofarads to farads, with common practical units including pF, nF, and µF.