HV Exit Exam • Set 7 Question 20 of 30

Which of the following contact metals exhibits the lowest minimum arcing voltage threshold?

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Direct Answer

Option D: Silver (~12 V)

Silver has a low ionization potential and low work function, giving it a lower minimum arcing voltage (~12 V) compared to refractory materials like tungsten, carbon, or graphite.

All Options

Carbon

Graphite

Tungsten

Silver (~12 V) (Correct Answer)

Detailed Explanation & Context

Silver has a low ionization potential and low work function, giving it a lower minimum arcing voltage (~12 V) compared to refractory materials like tungsten, carbon, or graphite.

Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • High Voltage Safety Officer & Switchgear Operations (HV).

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