Which resistor type is used to adjust voltage?

Which resistor type is used to adjust voltage?

• A. Rheostat
• B. Potentiometer
• C. Preset variable resistor
• D. Capacitor

Answer: (B)

A potentiometer is the resistor type used to adjust voltage because it acts as a voltage divider with a movable contact. With three terminals, the ends of the resistive track provide the input and ground, and the wiper taps off a variable fraction of that voltage. Turning the knob moves the wiper and changes the ratio, so the output voltage can be set to a desired level in the circuit. A rheostat changes resistance with two terminals to adjust current, not to provide a tunable output voltage in a divider configuration. A preset variable resistor is a small, trim version of a pot used for calibration rather than user adjustment during normal operation. A capacitor stores charge and shapes voltage over time, but it doesn’t offer a controllable voltage level in the same way a potentiometer does.

A potentiometer is the resistor type used to adjust voltage because it acts as a voltage divider with a movable contact. With three terminals, the ends of the resistive track provide the input and ground, and the wiper taps off a variable fraction of that voltage. Turning the knob moves the wiper and changes the ratio, so the output voltage can be set to a desired level in the circuit.

A rheostat changes resistance with two terminals to adjust current, not to provide a tunable output voltage in a divider configuration. A preset variable resistor is a small, trim version of a pot used for calibration rather than user adjustment during normal operation. A capacitor stores charge and shapes voltage over time, but it doesn’t offer a controllable voltage level in the same way a potentiometer does.