Capacitors
What is capacitance?
Ability of a capacitor to store a charge
What is inductance
-Ability to generate a voltage due to a change in current
-property of a circuit that opposes a change in current
What is capacitive reactance and what is it represented by?
Opposition to current flow caused by a capacitor- Xc
The Hypotenuse of an impedance triangle represents what?
Impedance/ total opposition to current flow
What is impedance and what does it consist of?
total opposition to current flow, resistance and reactance.
What 3 factors determine the capacitance of a capacitor?
Surface area of plates, distance between plates, and rating of dielectric
What components make up a typical inductor?
coil of wire, iron core
What is inductive reactance and what is it represented by?
Opposition to current flow caused by an inductor- XL
A 120V 60 Hz source is connected to a 30 microfarad capacitor, what is Xc?
88.42 ohms
What do capacitors oppose a change of?
Voltage
Does capacitance increase or decrease when adding capacitors in parallel
increase
What 3 things are needed for induction to take place?
magnetic field, conductor, relative motion
If a circuit is purely inductive or purely capacitive, what is the phase shift between voltage and current?
90 degrees
The base of an impedance triangle (x-axis) represents what?
Resistance
What acronym explains phase shift?
ELI the ICE man
Do capacitors generally have a high or low quality. (capacitance to resistance ratio)
high
An induced voltage is how many degrees out of phase with applied?
180
In purely reactive circuits whether it be inductive or capacitive, what type of power is produced? And what is it represented by?
Reactive power- VARs
A 120V 60 Hz source is connected to an Inductor with an XL of 120 ohms and an 80 ohm resistor in series. What is the current flow?
.83A
What forms of true power is dissipated in inductive circuits?
Hysteresis, heat I^2R, eddy currents
capacitors cause what phase shift
Current to lead by 90 degrees
Values of inductors add directly when wired in series or parallel?
Series
How many degrees out of phase are capacitive VARs and inductive VARs?
180
A 120V 60Hz source is connected to an Inductor, 5.7A flow through the inductor. What is the inductance of the coil?
.056H
What is the primary use of capacitors in industry?
Power factor correction