In the SI system, the multiple 10-18 is the prefix of _______.

This question was previously asked in
RPF SI (2018) Official Paper (Held On: 19 Dec, 2018 Shift 1)
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  1. Atto
  2. Yocto
  3. AXA
  4. Yotta

Answer (Detailed Solution Below)

Option 1 : Atto
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The correct answer is Atto

Key Points

  • Atto is the prefix used in the SI system to denote a multiple of 10-18.
  • The SI system, or International System of Units, uses standardized prefixes to represent various orders of magnitude.
  • The prefix Atto is represented by the symbol "a".
  • Other common SI prefixes include kilo (103), mega (106), and giga (109).
  • The use of standardized prefixes helps in maintaining consistency and clarity in scientific and technical communication.

Additional Information

  • The SI system was established in 1960 by the General Conference on Weights and Measures (CGPM).
  • It is the most widely used system of measurement worldwide, employed in both everyday commerce and science.
  • The SI system comprises seven base units, including the meter (length), kilogram (mass), and second (time).
  • Prefixes in the SI system cover a wide range from yotta (1024) to yocto (10-24).
  • Adopting SI units and prefixes ensures uniformity and reduces the potential for confusion in global scientific and technical exchanges.
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