What term is a variable voltage divider with a movable contact arm so that any portion of the potential applied between its ends may be selected?

• A. Power
• B. Pole
• C. Proton
• D. Potentiometer

Answer: (D)

Potentiometer is a device that acts as a variable voltage divider with a movable contact arm, allowing you to select any portion of the voltage applied between its ends. It has a resistive element with two end terminals and a wiper that slides along the element. Moving the wiper changes the resistance on either side and taps off a fraction of the total voltage at the wiper, which you can use as the output. This makes it ideal for adjusting signal levels, biasing, or calibration. The other terms don’t fit this role: power is the rate of energy transfer, not a divider; a proton is a subatomic particle; a pole is a switch or magnetic concept, not a variable divider.