onemillifarad

One millifarad (abbreviated mF) is a unit of electrical capacitance in the metric system. It equals one thousandth of a farad, or 0.001 F. Because the farad is a relatively large unit for practical components, the millifarad is commonly used to describe larger capacitances. In terms of other SI prefixes, 1 millifarad is equal to 1,000 microfarads (μF).

In practice, capacitors with values on the order of millifarads are physically larger than typical small-signal capacitors. They are often aluminum electrolytic or film types and are used in applications such as power supply filtering, energy storage for transient loads, and timing or pulse circuits where a moderate amount of capacitance is required. Voltage ratings for millifarad-sized capacitors can range from a few volts to hundreds of volts, depending on the design requirements.

Electrical energy storage for a capacitor is given by E = 1/2 C V^2. For example, a 1 mF capacitor charged to 5 V stores about 0.0125 joules, while at 100 V it stores about 5 joules. This illustrates how increasing voltage has a substantial impact on energy storage even for millifarad-scale capacitances.

Similar to other capacitance units, the millifarad is primarily encountered in technical contexts and is less common in everyday consumer electronics, where values are more frequently described in microfarads. When discussing capacitors, engineers may specify numeric values in mF, μF, or F, depending on the required precision and scale.