Which term describes a resistor that does not change its resistance?

• A. Resistor (variable)
• B. Switch
• C. Relay
• D. Resistor (nonvariable)

Answer: (D)

Understanding fixed versus variable resistance is key. A resistor that does not change its resistance is a fixed resistor, also called a nonvariable resistor. Its resistance stays the same across the usual operating range, so Ohm’s law V = IR gives a predictable current for a given voltage. A resistor that can change its resistance would be a variable resistor, which isn’t what’s described here. A switch or a relay isn’t defined by resistance—they control whether the circuit is connected or powered, not a constant resistance value. So the term that best describes a resistor whose resistance stays the same is nonvariable (fixed) resistor.