26201 Alternating Current Flashcard

Front

What is reactive power?

Back

Reactive power is the power that oscillates between the source and the load, and is always 90° out of phase with true power.

Front

What causes self-induced voltage in an inductor?

Back

Self-induced voltage across an inductance is produced by a change in current with respect to time.

Front

How do you calculate frequency from the time for one cycle?

Back

Frequency (f) is calculated as f = 1/T, where T is the time for one cycle. If T = 0.1 seconds, then f = 10Hz.

Front

What is the voltage across capacitors in series?

Back

Each of three equal capacitors in series has one-third the applied voltage.

Front

In a circuit with capacitance and resistance, how does current relate to voltage?

Back

In such a circuit, the current will lead the voltage by some angle between 0° and 90°.

Front

What is the phase relationship between true power and reactive power?

Back

Reactive power is always 90° out of phase with true power.

Front

What is the unit of reactive power?

Back

Reactive power is measured in volt-amperes reactive (VAR).

Front

What happens to voltage in a series circuit with equal capacitors?

Back

In a series circuit with equal capacitors, the voltage is divided equally among the capacitors.

Front

What is the relationship between frequency and period?

Back

Frequency is the reciprocal of the period (T), expressed as f = 1/T.

Front

What is the effect of resistance on current in an AC circuit?

Back

Resistance affects the phase angle between voltage and current, causing the current to lag behind the voltage.