Questions

Multiple-choice questions you can practise one by one. Open a question, tap an answer and see at once whether it is right. For a random set, try Quick practice.

941 questions

• Why can glass be used in electrical insulators despite being mechanically brittle?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which property of steatite makes it useful for insulating supports in electrical equipment?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is porcelain widely used for outdoor electrical insulators?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• What is a major limitation of asbestos that has led to strict controls on its use?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is mica suitable for insulation in equipment exposed to high temperatures?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why are silicone resins useful in electrical insulation exposed to elevated temperatures?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which property of melamine-based thermosetting materials is useful in electrical accessories?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which property distinguishes Bakelite from a typical thermoplastic when it has been fully cured?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is epoxy resin commonly used for encapsulating electrical components?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which application is particularly associated with polystyrene because of its dielectric properties?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which feature makes cross-linked polyethylene, or XLPE, suitable for power cables?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is PVC widely used for cable insulation?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why were PCB-containing insulating liquids such as traditional Pyranol restricted or phased out in many applications?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which test is commonly used to assess the ability of transformer oil to withstand electrical stress?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is a high flash point desirable in transformer oil?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which condition is most likely to reduce the dielectric strength of transformer oil?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which two functions are normally performed by mineral transformer oil?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Why is SF6 used in gas-insulated switchgear to achieve compact construction?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which precaution is especially important when handling SF6 equipment after an internal electrical arc?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium

• Which characteristic of SF6 makes it particularly useful for interrupting current in high-voltage switchgear?

  Electrical Engineering Materials › Unit 3: Insulating Materials · Medium