Understanding AC Power in Purely Capacitive Circuits

What components are present in a purely capacitive circuit?

• Only capacitors

• Resistors and inductors

• Capacitors and resistors

• Capacitors and inductors

In a purely capacitive circuit, how does the current relate to the voltage?

• Current lags voltage by 90 degrees

• Current leads voltage by 90 degrees

• Current and voltage are in phase

• Current and voltage are out of phase by 180 degrees

What is the phase angle between voltage and current in a capacitive circuit?

• 180 degrees

• 90 degrees

• 45 degrees

• 0 degrees

How is average power calculated in a capacitive circuit?

• RMS voltage times RMS current

• Peak voltage times peak current

• RMS voltage times RMS current times sine of phase angle

• RMS voltage times RMS current times cosine of phase angle

What is the cosine of the phase angle in a purely capacitive circuit?

• 0.5

• 0

• 1

• -1

Why is the average power in a capacitive circuit zero?

• Because power is always positive

• Because positive and negative powers cancel each other out

• Because voltage and current are always zero

• Because the circuit does not consume power

During which part of the cycle is power positive in a capacitive circuit?

• When voltage is positive and current is negative

• When both voltage and current are negative

• When voltage is negative and current is positive

• When both voltage and current are positive

What mnemonic is used to remember the phase relationship in capacitive circuits?

• ELI the ICE man

• HEIST the ICE man

• ICE the ELI man

• ICE the HEIST man

What does a negative power value indicate in a capacitive circuit?

• Power is not flowing

• Power is being stored

• Power is flowing from the load back to the source

• Power is flowing from the source to the load

In a capacitive circuit, when is power flowing from the source to the load?

• When power is negative

• When power is positive

• When power is zero

• When power is alternating