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p–V diagram for the ideal Diesel cycle.The cycle follows the numbers 1–4 in clockwise direction. The image shows a p–V diagram for the ideal Diesel cycle; where is pressure and V the volume or the specific volume if the process is placed on a unit mass basis.
The cutoff frequency is found with the characteristic equation of the Helmholtz equation for electromagnetic waves, which is derived from the electromagnetic wave equation by setting the longitudinal wave number equal to zero and solving for the frequency. Thus, any exciting frequency lower than the cutoff frequency will attenuate, rather than ...
Figure 2 illustrates the approximation. The x-axis is the ratio τ 1 / τ 2 on a logarithmic scale. An increase in this variable means the higher pole is further above the corner frequency. The y-axis is the ratio of the OCTC (open-circuit time constant) estimate to the true time constant.
Alpha cutoff frequency, or is the frequency at which the common base DC current gain drops to 0.707 of its low frequency value. The common base DC current gain is the ratio of a transistor's collector current to the transistor's emitter current , or α = i C i E {\displaystyle \alpha ={\frac {i_{C}}{i_{E}}}} .
where is the wavelength expressed in millimeters and F # is the lens' focal ratio. As an example, a telescope having an f /6 objective and imaging at 0.55 micrometers has a spatial cutoff frequency of 303 cycles/millimeter. High-resolution black-and-white film is capable of resolving details on the film as small as 3 micrometers or smaller ...
Higher-order passive filters can also be constructed (see diagram for a third-order example). A third-order low-pass filter (Cauer topology). The filter becomes a Butterworth filter with cutoff frequency ω c =1 when (for example) C 2 =4/3 farad, R 4 =1 ohm, L 1 =3/2 henry and L 3 =1/2 henry.
The response value of the Gaussian filter at this cut-off frequency equals exp(−0.5) ≈ 0.607. However, it is more common to define the cut-off frequency as the half power point: where the filter response is reduced to 0.5 (−3 dB) in the power spectrum, or 1/ √ 2 ≈ 0.707 in the amplitude spectrum (see e.g. Butterworth filter).
In electronics, cut-off is a state of negligible conduction that is a property of several types of electronic components when a control parameter (that usually is a well-defined voltage or electric current, but could also be an incident light intensity or a magnetic field), is lowered or increased past a value (the conduction threshold).