Which job can a capacitor perform in electrical work?
a.
Produce large current pulses
b.
Timing circuits
c.
Power factor correction
d.
All of the above
The correct answer is: All of the above
A capacitor consists of two conductors, usually referred to as plates separated by an insulator called the
? .
a.
barrier
b.
dielectric
c.
partition
d.
semi-conductor
The correct answer is: dielectric
Which physical factor determines the amount of capacitance?
a.
Area of the plates
b.
Distance between the plates
c.
Type of dielectric
d.
All of the above
The correct answer is: All of the above
The unit of capacitance is the ? and is symbolized by the letter ? .
a.
farad / F
b.
henry / H
c.
hertz / F
d.
ohm / Z
The correct answer is: farad / F
A capacitor has the capacitance of one ? when a change of one volt across its plates results in the
movement of one coulomb of electrons.
a.
farad
b.
microfarad
c.
milifarad
d.
picofarad
The correct answer is: farad
The flow of electrons through the insulating material of a capacitor is called ? .
a.
breakdown
b.
conduction
c.
crossover
d.
leakage
The correct answer is: leakage
? charge is the term used to describe the stationary charge stored in a capacitor.
a.
Capacitive
b.
Electromagnetic
c.
Electrostatic
d.
Static
The correct answer is: Electrostatic
If the electrical stress across a capacitor is excessive, it will be destroyed. Therefore, the ? rating of
capacitors should never be exceeded.
a.
current
b.
farad
c.
ohm
d.
voltage
The correct answer is: voltage
Match the term that completes the following statements.
A 120-VAC source is applied to a capacitor. The ? rating on the capacitor would have to be a minimum of 170 volts DCWV.
Air has a ? constant of 1.
The dielectric in the reference text table with the ? constant is ceramic with a dielectric constant of up to 7,500.
When the dielectric of a capacitor is broken down, excessive ? will flow through the dielectric, shorting it.
Possible answers
voltage
highest
dielectric
current
voltage
dielectric
highest
current
? capacitors can be used in either AC or DC circuits.
a.
Electrolytic
b.
Non-polarized
c.
Oil-filled
d.
Polarized
The correct answer is: Non-polarized
? capacitors are often used in motor circuits.
a.
Oil-filled non-polarized
b.
Paper non-polarized
c.
Polarized
d.
Variable
The correct answer is: Oil-filled non-polarized
Capacitors ? at an exponential rate.
I. charge
II. discharge
a.
I. only
b.
II. only
c.
I. & II.
d.
Neither
The correct answer is: I. & II.
When a graph is used to represent the rate-of-charge of a capacitor, it is broken down into ? time
constants.
a.3
b.5
c.7
d.9
The correct answer is: 5
During each time constant, the curve will see a change equal to ? of the amount of voltage left to
reach the fully charged state.
a.
5%
b.
36.2%
c.
62.3%
d.
63.2%
The correct answer is: 63.2%
The length of one time constant is dependent on the ? of the capacitor and the resistance in series
with the capacitor.
a.
current rating
b.
farad rating
c.
voltage rating
d.
all of the above
The correct answer is: farad rating
Drag the terms below to the appropriate locations to create the formula to find a capacitors time
constant.
T = ?
C/R
R x C
R/C
no answer
If an oil-filled capacitor has a terminal with an identification mark, this mark indicates that the terminal is
connected to the plate that is located ? the outer metal container or can.
a.
farther from
b.
nearer to
The correct answer is: nearer to
Electrolytic capacitors are the ? type.
a.
non-polarized
b.
oil-filled
c.
paper
d.
polarized
The correct answer is: polarized
This symbol represents a(n) ? capacitor.
a.
non-polarized
b.
oil-filled
c.
paper
d.
polarized
The correct answer is: polarized
Capacitors often have their farad value and ? rating printed on them.
a.
current
b.
reactance
c.
voltage
d.
all of the above
The correct answer is: voltage
Which is/are the proper safety rule(s) for working on circuits containing capacitance?
a.
Be sure to discharge the circuit capacitance after the circuit is turned off.
b.
Observe polarity marks when connecting capacitors to the circuit.
c.
Be sure the capacitor's voltage rating is greater than the peak voltage present in the circuit.
d.
All of the above.
The correct answer is: All of the above.