Caupayan,
Jedda Anne G. BSEd-4
Capacitors
Capacitors are really special and if you will ask me what makes it
special, I must say it is their ability to store energy. They are like a fully
charged electric battery. We call them as “caps” and they have all sorts of
critical applications in circuits. We can usually apply and observe them in
local energy storage, complex signaling filtering and voltage spike
suppression.
These are
images of capacitors:
Retrieved from: https://goo.gl/1fcDfO
Capacitor is an electronic device that can store energy. It is a
passive two-terminal device and can be very useful as an electrical component.
Just like the other electronic devices capacitor has also several features that
make it useful and important like the proportionality of the voltage to the
current. Those circuits that have capacitors show frequency-dependent behavior
so that circuits that intensify certain frequencies selectively can be
building. Capacitors occur as you would expect.
Circuit Symbols:
Drawing a capacitor in schematic has two common ways. They always have
two terminals, which go on to connect to the whole circuit. The capacitors
symbol composed of two parallel lines, which are either flat or curved; both
lines should be parallel to each other, close, but not touching.
Retrieved from: https://goo.gl/3j7lO1
(1) and (2) are standard capacitor circuit
symbols. (3) is an example of capacitors symbols in action in a voltage
regulator circuit.
The symbol
with the curved line (#2 in the photo above) shows that the capacitor is
polarized, it means that it’s probably an electrolytic capacitor.
Other
circuit symbols:
Capacitance Units
We cannot expect that all capacitors are
created equally. One capacitor is built to have a specific amount of
capacitance. The capacitance of a capacitor will tell us how much charge it can
store. More capacitance means more capacity to store charge. The standard unit
of capacitance is called the farad which is abbreviated as F.
Prefix Name
|
Abbreviation
|
Weight
|
Equivalent Farads
|
Picofarad
|
pF
|
10-12
|
0.000000000001 F
|
Nanofarad
|
nF
|
10-9
|
0.000000001 F
|
Microfarad
|
µF
|
10-6
|
0.000001 F
|
Milifarad
|
mF
|
10-3
|
0.001 F
|
Kilofarad
|
kF
|
103
|
1000 F
|
.
Voltage-Current
Relationships in Capacitors:
There is a relationship between the
voltage across the capacitor and the charge on a capacitor. Charge and voltage
are linearly related.
Q = C V
where:
V = voltage across the capacitor
Q = charge on the
plate
C = capacitance of the
capacitor.
The relationship between the charge on
a capacitor and the voltage across the capacitor is linear C, called the
capacitance.
Q = C V
When V is measured in volts, and Q is
measured in coulombs, then C has the units of farads. Farads are really
coulombs/volt.
The relationship, Q = C V, is the most
important thing you can know about capacitance. There are other details you may
need to know at times, like how the capacitance is constructed, but the way a
capacitor behaves electrically is determined from this one basic relationship.
Circuit Diagram:
Retrieved from: https://goo.gl/s9byQF
Capacitors Activity
I. Objectives: At the end of this activity, you will be able to:
a. determine the function of capacitors in electronic appliances,
b. determine the voltage drop of the bulb with capacitor,
c. create a circuit diagram of capacitors in series and parallel circuits.
II. Materials
Capacitors (4700uF)
Resistors (5500 Ω , 180 Ω)
AC-DC converter
alligator clips
stopwatchmultitester
III. Procedure:
1. Two capacitors of the
same amount will be used.2. A 20-ohm bulb is used.
3. The bulb and the
capacitors are connected in series applying a certain voltage output.
4. The voltage drop in
the bulb and capacitors is determined.
5. The procedure is
repeated with using 5 different voltage output.
6. The entire procedure
is repeated but with the components connected in parallel.
7. This time, 3 different
voltages will be applied.
8. The brightness of
light is observed.
9. The data are recorded
in the table.
IV. Data and Result:
Table 1: Capacitors in Series Circuit
VOUT
|
VBULB
|
Voltage drop, Capacitor (470uF )
|
REMARKS
|
|
VC1
|
VC2
|
|||
3.3 V
|
2X10-3 V
|
1.1 V
|
1.6 V
|
No light
|
5.2 V
|
3X10-3 V
|
1.8 V
|
2.6 V
|
No light
|
7.5 V
|
4X10-3 V
|
4.2 V
|
2.8 V
|
No light
|
9.3 V
|
5X10-3 V
|
5.0 V
|
3.4 V
|
No light
|
12 V
|
6X10-3 V
|
6.8 V
|
3.8 V
|
No light
|
Table 2: Capacitors in Parallel Circuit
VOUT
|
VBULB
|
Voltage drop, Capacitor (470uF )
|
REMARKS
|
|
VC1
|
VC2
|
|||
3.2 V
|
3.2 V
|
3.0 V
|
3.0 V
|
Dim
|
5.2 V
|
5.2 V
|
5.2 V
|
5.2 V
|
Bright
|
7.3 V
|
7.3 V
|
7.3 V
|
7.3 V
|
Brightest
|
IV. Guide Questions:
1. What is the voltage drop of the bulb in series circuit with capacitor?
Answer: The voltage drop of the bulb in series circuit with capacitor decreases as the voltage ouput increases.
2. What is the voltage drop of the bulb in parallel circuit with capacitor?
Answer: The voltage drop of the bulb in parallel circuit with capacitor increases as the voltage output increases.
V. Conclusion
Based on this activity, I learned that the bulb will light the brightest when the voltage output is in the highest value also but in a parallel circuit.
Walang komento:
Mag-post ng isang Komento