AC - Unit 20
The JAN standard is used to mark a capacitor intended for _____. a. military b. industrial c. laboratory d. civilian
a. military
In a capacitor, the voltage difference between the plates controls the _____. a. thickness of the dielectric b. amount of current flow through the capacitor c. amount of dielectric stress d. area of the plates
c. amount of dielectric stress
A device that opposes a change of voltage is a(n) _____. a. diode b. inductor c. capacitor
capacitor
When a capacitor is connected in a circuit with a resistor, the amount of time needed to charge the capacitor is called the _____. a. RC time variable b. CR time variable c. CR time constant d. RC time constant
d. RC time constant
A charge curve for a capacitor is divided into _____ time constants. a. two b. three c. four d. five
d. five
The farad is symbolized by the letter _____. a. C b. F c. Q d. V
f
A capacitor is constructed by separating two metal conductors called _____ with an insulating material called a(n) _____. a. electrolytes, ceramic b. dielectrics, plate c. ceramics, electrolyte d. plates, dielectric
plates, dielectric
In a capacitor, the amount of dielectric stress is proportional to the _____. a. thickness of the dielectric b. voltage difference between the plates c. distance between the plates d. current flow through the capacitor
voltage difference between the plates
A 100 mF capacitor and a 3.6 k W resistor are connected in series. How long will it take for the capacitor to change its charge completely? a. 1.8 s b. 2.3 s c. 3.8 s d. 4.3 s
a. 1.8 s
Variable capacitors normally have a dielectric of _____. a. air b. mica c. glass d. Teflon
a. air
A HIPOT is a test set used to test capacitor _____. a. dielectric b. tolerance c. capacitance d. leads
a. dielectric
The material between the plates is rated by a value called the _____. a. magnetic variable b. dielectric constant c. dielectric variable d. magnetic constant
b. dielectric constant
Energy in a capacitor is stored as a(n) _____. a. circulating current b. electrostatic charge c. magnetic field d. electromagnetic field
b. electrostatic charge
Polarized capacitors _____. a. must be used with AC only b. must be used with DC only c. can be used with either AC or DC d. none of the above
b. must be used with DC only
Nonpolarized capacitors _____. a. must be used with AC only b. must be used with DC only c. can be used with either AC or DC d. none of the above
c. can be used with either AC or DC
Polarized capacitors are also known as _____ capacitors. a. variable b. bipolar c. electrolytic d. electroplated
c. electrolytic
Capacitors charge and discharge at a(n) _____ rate. a. linear b. geometric c. exponential d. sinusoidal
c. exponential
The unit capacitance is the _____. a. coulomb b. ohm c. farad d. henry
c. farad
Increasing the surface area of the plates will cause the capacitance of a capacitor to _____. a. decrease b. stay the same c. increase
increase
In some capacitors there is a small amount of current that flows from one plate, through the dielectric material to the other plate. This current is called _____ current. a. conduction b. electrostatic c. leakage d. electrolytic
leakage