Resistors Flashcards
Carbon film resistor
a resistor that is produced by coating a nonconductive material with a film of carbon
Composition carbon resistor
resistors that are made by mixing carbon with other compounds to produce a substrate that has a known resistance
Fixed resistor
resistor that has a value that cannot be changed
Metal film resistor
resistor that is produced by coating a nonconductive material with a film of metal
Metal glaze resistor
resistor that is produced by applying a mixture of metal and glass to a nonconductive material
Multiturn variable resistor
variable resistor that requires multiple turns to change their resistance values
When is a multiturn variable resistor used
when a precise control of measurement is required
Potentiometer
variable resistor that has a sliding contact that is used as a voltage divider
Rheostat
variable resistor
Tolerance
amount of variation from a standard value that is permissible
Variable resistor
resistor whose resistance value can be varied between its minimum and its maximum values
Voltage divider
circuit that generally is constructed by connecting resistors in series to produce desired voltage drops across the resistors
Wire wound resistors
resistors that are constructed by winding resistive wire around a nonconductive material
Two reasons resistors are used
limit current flow
voltage dividers
How is resistance related to area of a resistor
they are inversely proportional (if area increases, resistance decreases)
How is resistance related to length of a resistor
they are directly related (if length increases resistance increases)
List the types of fixed resistors
composition carbon
metal film
metal glaze
carbon film
wire wound
What is/are disadvantage(s) of composition carbon resistors
they change value as they age or if they are overheated
What are advantages of metal film resistors
their value doesn’t change with age
have better tolerance
What determines the resistance of a wire wound resistor
type of material used to make the wire
diameter of the wire
length of the wire
Why are carbon resistors popular in most applicatons
they are inexpensive
How is a metal glaze resistor made
combining metal with glass
When are wire wound resistors used
when a higher power rating is needed
What is a major advantage of wire wound resistors
they can operate at a higher temperature than other resistors
