4. Power Systems and Grids
Ac Power — Quiz
Test your understanding of ac power with 5 practice questions.
Practice Questions
Question 1
What expression defines the RMS value of a sinusoidal voltage with peak amplitude $V_\text{peak}$?
Question 2
A sinusoidal voltage is given by $v(t)=170\cos(\omega t)\,\mathrm V$. What is its RMS value?
Question 3
What does a lagging power factor indicate about the phase relationship between current and voltage?
Question 4
A single-phase load draws real power $P=4\,\mathrm{kW}$ and apparent power $S=5\,\mathrm{kVA}$. What is its power factor?
Question 5
A load consumes $P=6\,\mathrm{kW}$ at $\mathrm{pf}=0.8$ lagging from a $400\,\mathrm V$ supply. What is the supply current?