The true power indicated by a wattmeter depends on the current flow through the load, the magnitude of the voltage across the load, and what other factor?
• True power vs. apparent power in AC circuits • Relationship between voltage, current, and phase angle • How a wattmeter measures power in an AC system
• Think about what makes the actual usable power in an AC circuit different from just volts × amps. • Which option relates to the phase relationship between current and voltage in an AC load? • Ask yourself: what quantity must a wattmeter effectively account for to show real (true) power instead of just apparent power?
• Identify which choice is directly tied to the phase angle between voltage and current. • Eliminate any options that describe mechanical properties of the meter rather than an electrical property of the load. • Confirm which factor appears in the formula for real power in AC circuits: (P = V \times I \times ?).
No comments yet
Be the first to share your thoughts!