Wiring and componentsQuestion 69 of 1506

A selector switch must switch an extremely small signal current in an electronic circuit. Which contacts should be specified?

  1. Silver-cadmium contacts
  2. Gold-plated contacts
  3. Plain copper contacts
  4. Mercury contacts in any position
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Correct answer: Gold-plated contacts

Gold is a noble metal and has extremely low wetting current needs.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 4.2: Switch Contact Design

Practice wiring and components

Questions last reviewed: 18 October 2026