Which statement describes a potentiometer?

• A. Same as rheostat but uses 4 leads
• B. A diode
• C. Same as rheostat but uses 3 leads to resist current flow
• D. A capacitor

Answer: (C)

A potentiometer is a three-terminal adjustable resistor. Its resistance between the two end terminals is fixed, while the wiper provides a variable tap along that track. If you wire it as a two-terminal device (the wiper and one end), it behaves like a rheostat, varying resistance and thus controlling current. Because it has three leads, you can also use all three to create a voltage divider, taking a portion of the input voltage at the wiper. So describing it as the same as a rheostat but with three leads to resist current flow captures its essential role and the extra terminal that enables voltage division. The other options don’t fit since a potentiometer is not a diode or a capacitor, and it does not require four leads.