Which statement best describes the purpose of impedance matching between a sensor and a data acquisition input?

• A. To maximize signal transfer and preserve bandwidth
• B. To minimize power loss in long cables
• C. To maintain wanted amplitude, minimize reflections and distortion, and preserve bandwidth
• D. To eliminate the need for grounding

Answer: (C)

Impedance matching between a sensor and a data acquisition input is about keeping the signal intact as it travels through the connection. When the source and load impedances are well matched to the transmission path, reflections at the cable ends are minimized. Those reflections can distort the waveform, alter the amplitude, and eat into the usable bandwidth. So the strongest, most complete statement is that matching preserves the wanted amplitude, minimizes reflections and distortion, and maintains the full bandwidth of the signal. Other options only partially describe the effect or miss the core goal: maximizing power transfer alone can ignore distortion; focusing on power loss in long cables isn’t about signal integrity; grounding is unrelated to the matching objective.