Physics Finals RLC and Resonance

charge

A capacitor will _ when connected to a dc voltage source

discharge

A capacitor will _ when a wire is connected across a charged capacitor

RC time constant

when a capacitor charges or discharges through a resistance, a certain time is required to charge or discharge fully

time constant

determines the rate at which the capacitor charges or discharges

5

__ time constant intervals are generally accepted as the time fully charge or discharge a capacitor and are called transient time

Reactance

property of capacitor that opposes the flow or current in AC circuit

Capacitive Reactance

opposite to sinusoidal current, expressed in ohms

instantaneous capacitor current

is equal to the capacitance times the instantaneous rate of change of voltage across the capacitor

Instantaneous, True, Reactive

Types of power in capacitive circuit

Instantaneous power

can either be negative or positive, product of instantaneous voltage and instantaneous current

True Power

always zero purely capacitive/inductive current

True Power

Equivalent to the power in the winding resistance

power factor

=cosθ

Reactive factor

=sinθ

Power factor and reactive factor

used to indicate how small or large the AC circuit dissipates power

purely reactive

PF=0

purely resistive

PF=1

1

Desired PF

RL time constant

fixed time interval required for the current to make a change from one value to another

Inductive reactance

the opposition to sinusoidal current.

Quality Factor

the ratio of the reactive power in an inductor to the true power in the winding of the coil or the resistance in series with the coil. Ratio of power in L to the power in RW

low

At a very __ frequency, Xc is high and Xl is low and the circuit is predominantly inductive

Resonant Frequency

Frequency at resonance

Conductance

the reciprocal of resistance (GL)

susceptance

the reciprocal of inductive reactance (BL)

admittance

the reciprocal of impedance

tank circuit

the common term for a parallel resonant LC circuit is