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Basic Electronics Engineering I
:: Variable Resistors
 
     A variable resistor has a resistance that can be varied. Variable resistors are used to divide voltage and to control current.
 
:: Potentiometer & Rheostat
 
   A potentiometer is a three-terminal variable resistor used to divide voltage. It is used as an adjustable voltage divider. Typical applications of a potentiometer are volume control for radio or TV receivers, or applied voltage control across load in a circuit.
 
     A rheostat is a two-terminal device used to control current. A potentiometer can be used as a rheostat by connecting terminal 3 to either terminal 1 or terminal 2. Both symbols for a rheostat are equivalent
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