Which option describes the impedance value for twisted-pair cabling?

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Multiple Choice

Which option describes the impedance value for twisted-pair cabling?

The main idea is the characteristic impedance of twisted-pair cables, which is 100 ohms and is described as balanced. Twisted-pair cables (like Cat 5e/6/6A) are designed to present a nominal 100-ohm impedance to a transmitter and receiver, with the two conductors carrying equal and opposite signals to form a differential (balanced) pair. Matching this impedance is crucial to minimize reflections and maintain signal integrity over the cable lengths used in Ethernet. In contrast, coaxial cables use impedance values of either 50 ohms or 75 ohms, depending on the type, and fiber optic cables aren’t described by an impedance in the same way; 50/125 μm OM1 refers to a fiber class and core/cladding size, not to a twisted-pair impedance. So the correct description for twisted-pair impedance is 100 ohms balanced.

The main idea is the characteristic impedance of twisted-pair cables, which is 100 ohms and is described as balanced. Twisted-pair cables (like Cat 5e/6/6A) are designed to present a nominal 100-ohm impedance to a transmitter and receiver, with the two conductors carrying equal and opposite signals to form a differential (balanced) pair. Matching this impedance is crucial to minimize reflections and maintain signal integrity over the cable lengths used in Ethernet.

In contrast, coaxial cables use impedance values of either 50 ohms or 75 ohms, depending on the type, and fiber optic cables aren’t described by an impedance in the same way; 50/125 μm OM1 refers to a fiber class and core/cladding size, not to a twisted-pair impedance. So the correct description for twisted-pair impedance is 100 ohms balanced.

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