Resistor Basics
what is resistance
The electrical resistance of an electrical element measures its opposition to the passage of an electric current
how should the power rating of resistors be chosen
it should be about twice the power consumption needed
what is a resistor
A resistor is a two-terminal passive electronic component which implements electrical resistances a circuit element
what is one Mnemonic for remembering the sequence of the resistor color code
Bad Boys Ravish Only Young Girls But Violet Gives Willingly
how does a resistor function
When a voltage V is applied across the terminals of a resistor, a current I will flow through the resistor in direct proportion to that voltage
since a resistor acts as a current limiter what is one way it can be seen as in a plumbing analogy
a flow constrictor
in order to measure a resistor of less than 1 ohm with accuracy what does it require
a four terminal connection
if the average power dissipated by a resistor is more than its power rating what happens
damage to the resistor may occur permanently altering its resistance and causing erratic behavior or circuit failure
if a capacitor is a storage device how can adding a resistor add a time delay
since a capacitor could be seen as a bucket and a resistor as flow constrictor, constricting more flow would increase the time it takes to fill the bucket
what does the power rating indicate
the amount of power a resistor can safely dissipate
what is the temperature coefficient
the change in resistance as the device warms
what is the unit of resistance
the ohm
what does the tolerance rating indicate
the precision of the resistor given as a percentage. Resistors within tolerance will only vary their resistance by the amount of tolerance
what is the function of a resistor
to limit current
how much power does most resistors in circuits dissipate
usually no more than 1/4 and sometimes 1/2 watt
how do you test resistors
with an ohmmeter
