Chapter 11: Capacitance
MULTIPLE CHOICE
1. Capacitance is present whenever two ____ are separated by an insulator.
a.
resistors
c.
capacitors
b.
conductors
d.
magnets
2. In a DC circuit, a capacitor acts as a(n) ____ circuit after its initial charge.
a.
open
c.
series
b.
closed
d.
parallel
3. The dielectric prevents ____ from moving between the plates.
a.
protons
c.
electrons
b.
neutrons
d.
atoms
4. The capacitor’s voltage is ____ the voltage of the voltage source.
a.
less than
c.
equal to
b.
greater than
d.
unrelated to
5. Doubling the plate area ____ the capacitance if all other factors remain the same.
a.
halves
c.
triples
b.
doubles
d.
quadruples
6. ____ capacitors consist of two metal foils separated by fine gauze or other absorbent material that is
saturated with a chemical paste.
a.
Electrolytic
c.
Ceramic
b.
Plastic
d.
Variable
7. The ____ capacitor is popular because it is inexpensive to produce. It is used for capacitors of 0.1
microfarad and smaller.
a.
electrolytic
c.
ceramic disk
b.
plastic
d.
variable
8. ____ capacitors come in all sizes and shapes. Types include padders, trimmers, and tuning capacitors.
a.
Electrolytic
c.
Ceramic disk
b.
Plastic
d.
Variable
9. Placing capacitors in series effectively increases the thickness of the dielectric, thereby ____ the total
capacitance.
a.
negating
c.
increasing
b.
doubling
d.
decreasing
10. It takes approximately ____ time constants to fully charge or discharge a capacitor.
a.
three
c.
five
b.
four
d.
six
COMPLETION
1. The basic unit of capacitance is the ____________________.
2. A(n) ____________________ is a measure of the effectiveness of a material as an insulator.
3. A(n) ____________________ capacitor is one whose capacitance can be changed either by varying
the space between plates (trimmer capacitor) or by varying the amount of meshing between two sets of
plates (tuning capacitor).
SHORT ANSWER
1. Describe how the type of dielectric material affects the capacitance of a capacitor. Describe a dialectric
constant and provide some examples.
2. An RC time constant reflects the relationship between time, resistance, and capacitance. Describe the
relationships. How is the time constant expressed?