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Open CalculatorAll Electrical and Computer: Power PE Equations (15)
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Capacitance of Parallel Plate Capacitor
Capacitance between two parallel plates.
basic -
Capacitor Current-Voltage Relationship
Relationship between current and voltage in a capacitor.
basicHigh Frequency -
Energy Stored in Capacitor
Energy stored in the electric field of a capacitor.
basic -
Complex Number in Rectangular Form
Represents a complex number in terms of its real and imaginary components.
basicHigh Frequency -
Effective Annual Interest Rate
Converts nominal annual interest rate to effective annual rate with compounding m times per year.
basicHigh Frequency -
Inductance
Inductance of a coil.
intermediate -
Energy Stored in Inductor
Energy stored in the magnetic field of an inductor.
basic -
Inductor Voltage-Current Relationship
Relationship between voltage and current in an inductor.
basicHigh Frequency -
Power Factor Correction Delta Q
Change in reactive power for power factor improvement.
intermediateHigh Frequency -
Straight-Line Depreciation
Calculates annual depreciation using straight-line method.
basicHigh Frequency -
Transformer Copper Losses
Total copper losses in transformer windings.
intermediateHigh Frequency -
Transformer Efficiency
Efficiency of power transformation.
basicHigh Frequency -
Transformer Input Power Factor
The input (primary) power factor is the cosine of the phase angle between voltage and current.
basicHigh Frequency -
Voltage Drop
Voltage drop in a line at unity power factor (negligible reactance).
basicHigh Frequency -
Voltage Regulation
Percentage voltage regulation.
basicHigh Frequency
Frequently Asked Questions
How do I use Capacitance of Parallel Plate Capacitor on the PE exam?
Remember that ε = εr × ε₀ where ε₀ = 8.854 × 10⁻¹² F/m. For air, εr ≈ 1. Common exam trap: forgetting to convert area units (mm² to m²) or using wrong permittivity value. Always check if relative or absolute permittivity is given.
How do I use Capacitor Current-Voltage Relationship on the PE exam?
This is the fundamental capacitor equation - memorize it! Remember that current leads voltage in capacitors (opposite of inductors). Watch units carefully - capacitance is often given in μF, mF, or nF. Zero current means constant voltage, and infinite current would mean instantaneous voltage change.
How do I use Energy Stored in Capacitor on the PE exam?
Remember the alternative forms: Energy = q²/(2C) = (1/2)Cv² = (1/2)qv. Know which variables you're given to choose the most efficient form. Watch units carefully - capacitance is often given in µF or pF.
How do I use Complex Number in Rectangular Form on the PE exam?
In AC circuit problems, the real part represents resistance and the imaginary part represents reactance. Capacitive reactance is negative, inductive reactance is positive. Always check if the problem asks for rectangular or polar form.
How do I use Effective Annual Interest Rate on the PE exam?
On PE exams, this equation appears in present worth and future worth problems. Always convert to effective rates before using in other economic formulas. Watch for problems mixing different compounding periods - convert all to same basis first.