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What is the best insulator?

For a given thickness, which has the highest breakdown voltage?

Air, mica, porcelain, hard rubber

2 Answers

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  • 1 decade ago
    Favorite Answer

    The absolute best insulator of both heat and electric current is a vacuum.

    Although to thermally insulate perfectly...you also need to enclose the vacuum in reflective boundaries...because there is one mode of heat transfer (radiation) that the vacuum can do nothing about.

  • ?
    Lv 7
    1 decade ago

    GLASS!!

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