Capacitance and Capacitive Reactance Flashcards
What is the material between the two plates of a capacitor called?
a dielectric
What type of capacitors can be used in ac circuits?
non-polarized
What can happen if a polarized electrolytic capacitor is connected improperly in a circuit?
it may explode
name four applications where capacitors are used
timers, rectifiers, power factor correction, motor starting
what is capacitance?
the ability to store electric charge
what is the symbol for capacitance?
c
what is the symbol for the unit of measurement of capacitance?
F
what three factors affect the capacitance of a capacitor?
area of plates, distance between plates, type of dielectric
what are the two ratings that describe the effectiveness of a dielectric?
strength, constant
on a capacitor rated at 300 WVDC, what does WVDC stand for?
working volts DC
What is the symbol for electric charge?
Q
What is the unit of measurement of electric charge and its symbol?
Coloumb, C
When the frequency of a circuit is increased, what happens to the capacitive reactance?
decreases
If a capacitor is replaced with one of smaller capacitance, what happens to the capacitive reactance of the circuit?
increases
In a capacitive ac circuit, how does the current rise and fall compared in time to the rise and fall of the voltage?
leads
