Which type of resistor is used in circuits where power requirements exceed 2 watts?

Which type of resistor is used in circuits where power requirements exceed 2 watts?

• A. Metal-film Resistors
• B. Ceramic Resistors
• C. Wire-wound Resistors
• D. Carbon-film Resistors

Answer: (C)

Power-handling capability drives the choice of resistor type. When a circuit needs to dissipate more than a couple of watts, you select a resistor designed to shed heat efficiently. Wire-wound resistors achieve this because their resistive element is a wire wound around a core, which creates a large surface area and a direct path for heat to be transferred to the surrounding air or mounting hardware. That construction supports higher wattage ratings and better thermal stability, making them the preferred option for power levels exceeding about 2 watts. Keep in mind that the winding introduces some inductance, which can matter in high-frequency or precision AC applications, but for purposes of handling higher power, this trade-off is usually acceptable. The other common resistor types are generally used for lower power levels: metal-film and carbon-film resistors are compact and precise but typically rated for smaller power dissipation, and while ceramic resistors cover a range of applications, wire-wound types are the standard go-to when heat and power handling are the primary concerns.

Power-handling capability drives the choice of resistor type. When a circuit needs to dissipate more than a couple of watts, you select a resistor designed to shed heat efficiently. Wire-wound resistors achieve this because their resistive element is a wire wound around a core, which creates a large surface area and a direct path for heat to be transferred to the surrounding air or mounting hardware. That construction supports higher wattage ratings and better thermal stability, making them the preferred option for power levels exceeding about 2 watts.

Keep in mind that the winding introduces some inductance, which can matter in high-frequency or precision AC applications, but for purposes of handling higher power, this trade-off is usually acceptable. The other common resistor types are generally used for lower power levels: metal-film and carbon-film resistors are compact and precise but typically rated for smaller power dissipation, and while ceramic resistors cover a range of applications, wire-wound types are the standard go-to when heat and power handling are the primary concerns.