DAY 3 Resistors Lecture Flashcards
Used in electrical circuits to control the amount of current flow by converting electrical energy into heat
Resistors
One _____ of resistance will allow one Amp of current to pass when one Volt of pressure is applied.
Ohm
There are 2 main types of Resistors:
Fixed Resistors
Variable Resistors
Resistive value is ______, it ______ be varied/changed.
answer;
Fixed
answer;
cannot
Most common types
Composition Type - used to control small amount of current (2 main types)
Carbon Composition Type - made of compressed graphite
- Film Composition Type:
Carbon-film – thin coating of carbon around an insulator
Metal film – Metal film wrapped around a ceramic core
Resistor 1st band represents
1st significant figure in ohmic value
Resistor 2nd band represents
2nd band 2nd significant figure
Resistor 3rd band represents
Multiplier (number of zeros)
Resistor 4th band represents
Tolerance (in %)
gold is plus or minus 5%
silver plus or minus 10%
if no fourth color , plus or minus 20%
The band colored black has a value of
0
The band colored brown has a value of
1
The band colored Red has a value of
2
The band colored Orange has a value of
3
The band colored Yellow has a value of
4
The band colored Green has a value of
5
The band colored Blue has a value of
6
The band colored Violet has a value of
7
The band colored Gray has a value of
8
The band colored White has a value of
9
The 4th band having no color has a value of
+-20%
The 4th band colored Silver has a value of
+-10%
The 4th band colored Gold has a value of
+-5%
If a resistor is less than 10 ohms
Use gold or silver multiplier
Gold multiply by .1
Silver multiply by .01
- Varies the current
- Cockpit lighting
- Has two terminals
Rheostat
- Changes the amount of voltage in a circuit
- Used as a voltage divider
- Three terminals
- Connectors are usually soldered because potentiometer action is dependent on resistance and the resistance must be kept at a bare minimum
Potentiometer
