Complex numbers representing amplitude and phase of sinusoids, turning calculus into algebra.
A sinusoid V_m cos(ωt+φ) is represented by the complex phasor V=V_m∠φ. Derivatives become jω multiplication, converting ODEs to algebra. Phasor diagrams show relative phase of voltages and currents in steady state.
v=10cos(ωt+30°) is 10∠30°.
Phasors turn sinusoidal analysis into algebra, which makes AC circuits as easy to solve as DC circuits.
Complex numbers representing amplitude and phase of sinusoids, turning calculus into algebra.
Phasors turn sinusoidal analysis into algebra, which makes AC circuits as easy to solve as DC circuits.
A complex number representing the amplitude and phase of a sinusoid, with the time dependence handled implicitly.
When the circuit is linear and driven at a single frequency, so all voltages and currents share that frequency.
Typical applications include finding the current in an RL circuit driven by a 60 Hz supply, calculating the phase shift of a filter at one frequency and solving the voltages in an AC circuit with several reactive elements.
Study "RMS value" first (topic 38 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Same frequency required. Use RMS or peak consistently. Rotating vectors.
v=10cos(ωt+30°) is 10∠30°.
The next topic is "Impedance", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 39 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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