🔍 Key Concepts

• Common properties needed for relay contact materials (conductivity, resistance to arcing, mechanical durability) • Typical uses and advantages of tungsten, silver, and gold in electrical contacts • Why some relays may use different materials for different applications (high current vs low current, corrosion resistance, etc.)

💭 Think About

• For each metal listed, think about whether it is a good conductor and how it behaves under arcing or sparking conditions in a relay. • Consider which materials are often used for high-current, high-voltage switching versus low-current, low-voltage, or signal-level switching. • Ask yourself: Is there a single 'best' universal contact material, or do different relay applications call for different materials?

✅ Before You Answer

• Verify which of the listed metals are actually used in practice as contact materials in relays, not just theoretically possible. • Check which metals perform well under repeated arcing and high temperature at the contact surface. • Confirm whether all three metals have recognized uses in relay contacts, or if one is generally not used in that way.