# Dissipation factor

The loss factor (English: dissipation factor, abbreviated DF) describes in physical oscillations of different nature, including in electrical engineering and the rheology, the ratio of the lossy to lossless real part imaginary part of a complex quantity. The loss factor is equal to the tangent of the loss angle between the complex size and its imaginary part.

## Electrical Engineering

### Energy

The loss factor indicates how large are the losses in electrical components such as inductors and capacitors, or in the propagation of electromagnetic waves in matter ( eg, air). With "loss" here is meant the energy that is electrically or electromagnetically lost and, for example, into heat (dissipation ). These losses by the electromagnetic wave is attenuated.

For a more detailed illustration of the loss factor is considered a capacitor, which is connected to a voltage source with a sinusoidal voltage waveform over time. In such a condenser, a phase shift between voltage and current:

- An ideal capacitor having no losses, has a phase shift of ( radians)
- In a real capacitor which has losses, the phase shift of the loss angle is less than:

### Resonant circuit

As loss factor d ( damping; dissipation factor DF in English ) is also the inverse of the quality factor Q is in resonant circuits and filters:

See also coil quality.

## Rheology

In the rheology of the loss factor refers to the ratio between the loss modulus ( imaginary part) and storage modulus ( real part ):

- The higher the loss factor, the more approaches the behavior of a sample of the ideal - viscous liquid with Newtonian flow behavior at

- The lower the loss factor, the more the behavior is a sample to that of a perfectly elastic solid

- Wave
- Rheology