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Classified in Technology
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Ø
resistors
ØIt slows down and restricts the flow of
current
Ø
Ø It’s measured in Ohms (Ω)
Ø
Ø
There are two types:
FIXEd andVARIABLE
variable resistors
ØPOTENTIOMETER/RHEOSTAT
ü A type of resistor whose value can be
Modify by a moveable piece
ü
ü Can
Be used as volume controls on audio equipment, light dimmers
ØTHERMISTORS
ü They are resistances that depend on
TEMPERATURE
ü Two types:
üNTC
(Negative Temperature Coefficient). T R
üPTC
(Positive Temperature Coefficient). T R
ü Used
As temperature detectors in thermostats
Ø
LDR (LIGHT DEPENDENT RESISTOR)
Ø
ü The resistance varies according to the
Amount of light the resistor receives. Light
R
ü
ü Used
In cameras, photocopy machines, position sensors, street light control, night
Light control, etc
CAPACITORS
ØThey can store electric charge
Ø The value of a capacitor (CAPACITANCE) is
Measured in farads (F)
Ø Can be
Split into two groups: polarised (electrolytic) and unpolarised
Ø Capacitors are commonly used in
electronic devices to maintain power Supply
while batteries are being changed
SEMICONDUCTORS
ØThey are solid materials that depending
On the environmental conditions can act as conductors or as insulators
ØTwo
Types: intrinsicsemiconductors: Si, Ge and
Extrinsic (they have doping elements). Under research: Carbon and Graphene (grafeno)
DIODES
Ø A diode is formed by joining a type P
(gaps) crystal with a N crystal (electrons)
TRANSISTORS
ØThey are basic elements in electronic
Circuits, made from semiconductive materials
Ø They have three LEADS (TERMINALS): emitter, base
And collector
Ø They
Operate by small current flowing into the base
Ø They
Are used to amplify and switch
Electronic signals and electrical power
ØThey are basic elements in electronic
Circuits, made from semiconductive materials
Ø They have three LEADS (TERMINALS): emitter, base
And collector
Ø They
Operate by small current flowing into the base
Ø They
Are used to amplify and switch
Electronic signals and electrical power
-TYPES ØBipolar junction transistor (BJT)
And Field-effect transistor (FET)
the circuit is open so there isnt current in the base (Ib-0), transport is blocked--(Ic-0), light bulb off
If close the circuit there will be current in the base, the transistos will be plyfy and the light bulb wil be on.
2transistores---if the circuit is open Ib1-0-t1 blocked--Ib2-0-t2 blocked-Ic2-0-bulb off
if we cole the circuit - 3tB1-T1 is inamplification mode -T2 also amplifier -light bulb
interruptor-when the push botton is open there is not current in the base (transistor blockied) and the capacitor has not chargue. If we close the circuit the transistors will be working as an amplifier, the bulb will be on and the capacitor will chargue. When we open the circuit again the bulb will continue lighting because the capacitor will give the electicity to the base of transistor