Red Seal Electrician Practice
Signalling and communicationQuestion 39 of 1506

Why does a serial network need a higher signal frequency than a parallel one that sends the same data?

  1. Serial bits are larger than parallel bits, so they need more bandwidth
  2. Serial wires have less resistance, so they need a faster supply
  3. All the bits must pass one channel in the same time window
  4. Serial networks must use AC power to move each bit along the line
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Correct answer: All the bits must pass one channel in the same time window

In the text's 8-bit example, the frequency rises from 0.5 Hz to about 4 Hz.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 14.4: Electrical Signal Types

Practice signalling and communication

Questions last reviewed: 18 October 2026