Time constants and phase relationships: RLC time constants; definition; time constants in RL and RC circuits; phase angle between voltage and current; phase angles of series RLC; phase angle of inductance vs susceptance; admittance and susceptance

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2016-E5B: Time constants and phase relationships: RLC time constants; definition; time constants in RL and RC circuits; phase angle between voltage and current; phase angles of series RLC; phase angle of inductance vs susceptance; admittance and susceptance

2016-E5B01:
What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

One time constant

An exponential rate of one

One exponential period

A time factor of one

2016-E5B02:
What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

One time constant

One discharge period

An exponential discharge rate of one

A discharge factor of one

2016-E5B03:
What happens to the phase angle of a reactance when it is converted to a susceptance?

The sign is reversed

It is unchanged

It is shifted by 90 degrees

The susceptance phase angle is the inverse of the reactance phase angle

2016-E5B04:
What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

220 seconds

55 seconds

110 seconds

440 seconds

2016-E5B05:
What happens to the magnitude of a reactance when it is converted to a susceptance?

The magnitude of the susceptance is the reciprocal of the magnitude of the reactance

It is unchanged

The sign is reversed

It is shifted by 90 degrees

2016-E5B06:
What is susceptance?

The inverse of reactance

The magnetic impedance of a circuit

The ratio of magnetic field to electric field

A measure of the efficiency of a transformer

2016-E5B07:
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

14.0 degrees with the voltage lagging the current

68.2 degrees with the voltage leading the current

14.0 degrees with the voltage leading the current

68.2 degrees with the voltage lagging the current

2016-E5B08:
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

14 degrees with the voltage lagging the current

14 degrees with the voltage leading the current

76 degrees with the voltage leading the current

76 degrees with the voltage lagging the current

2016-E5B09:
What is the relationship between the current through a capacitor and the voltage across a capacitor?

Current leads voltage by 90 degrees

Voltage and current are in phase

Voltage and current are 180 degrees out of phase

Voltage leads current by 90 degrees

2016-E5B10:
What is the relationship between the current through an inductor and the voltage across an inductor?

Voltage leads current by 90 degrees

Current leads voltage by 90 degrees

Voltage and current are 180 degrees out of phase

Voltage and current are in phase

2016-E5B11:
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

14 degrees with the voltage leading the current

14 degrees with the voltage lagging the current

76 degrees with the voltage lagging the current

76 degrees with the voltage leading the current

2016-E5B12:
What is admittance?

The inverse of impedance

The term for the gain of a field effect transistor

The turns ratio of a transformer

The unit used for Q factor

2016-E5B13:
What letter is commonly used to represent susceptance?