EEUTI130 FQ1 B-KEY Quiz

Why is AC power more suitable than DC for large-scale transmission across long distances?

• AC systems operate at a lower voltage than DC, reducing transmission losses.

• AC systems can efficiently step up and step down voltage using transformers.

• AC systems require fewer protective components compared to DC systems.

In the sinusoidal voltage expression v(t) = Vim cos(ωt + θ), what does θ indicate?

• The maximum peak value of the waveform

• The rate at which the waveform oscillates per second

• The phase shift of the waveform relative to a reference point

Which measurement of an AC waveform represents the equivalent heating effect of a DC source?

• Peak voltage, indicating the highest instantaneous value

• RMS voltage, providing the effective power-carrying capability

• Average voltage, calculated over one complete cycle

Over a complete cycle, what is the algebraic average of a pure sinusoidal AC waveform?

• Equal to the peak value

• Half of the peak value

• Zero

What does the peak-to-peak value of an AC waveform represent?

• The highest absolute voltage or current in the cycle

• The total span between the maximum positive and maximum negative points

• The average magnitude of the waveform over time

Which inventor is best known for advocating direct current (DC) systems and opposing AC power distribution in the late 19th century?

• Thomas Edison

• Nikola Tesla

• James Clerk Maxwell

What is the primary function of a transformer in AC power systems?

• To regulate the frequency of an AC signal

• To adjust voltage levels efficiently for transmission and distribution

• To convert AC into DC for household use

Given a sinusoid with period T = 0.025 sec, what is its frequency f?

• 0.025 Hz

• 4 Hz

• 40 Hz

In an AC circuit, what is the role of reactive power?

• It accounts for real power consumed by purely resistive loads

• It directly determines the efficiency of the power factor

• It represents stored energy that cycles between the source and reactive components

In an AC circuit, what does the product of voltage and current represent when phase angle is ignored?

• The total power transferred, including both real and reactive components

• The actual energy dissipated as heat or useful work

• The energy temporarily stored in inductors and capacitors