Week 5 Flashcards
What is used to determine power in AC?
Effective or rms value of an AC waveform.
Why is rms used?
If peak voltage is used the average is zero as it is an AC Waveform.
Define rms value.
EQUIVALENT DC VALUE
of the AC waveform.
Resistor dissipates more or less heat in an AC or DC circuit?
Same
The phase shifts introduced by reactive elements result in a…
…reactive component of power.
The reactive component of power does…
…no useful work.
What does power factor describe?
Extent of the phase shift between
the voltage and the current.
Power factor is caused by…
…reactive elements.
What can power be dissipated by?
Only a resistor.
What can power not be dissipated by?
Inductor or a capacitor
In a pure resistive circuit v s and i s would be
In phase.
Lagging power factor:
net inductive circuit
Leading power factor:
net capacitive circuit
What is the power triangle?
Right-angled triangle
Describes distribution product of 𝑣 and 𝑖 throughout circuit.
What are the three sides of the power triangle?
The apparent power
𝑺 = 𝑣. 𝑖
The real power
𝑷 = 𝑣. 𝑖. cos ϕ
The reactive power
𝑸 = |𝑣. 𝑖. sin ϕ|
