Question

Which of the following is used as SI prefixes:

• A. Femto
• B. Atto
• C. Zepto
• D. All of the above

Answer 1

The correct option is D All of the above

Here femto, atto and zepto, all are used as a prefix in the SI system.

In metric systme, $1$ femtometer $={10}^{-15}$ meter, $1$ attometer $={10}^{-18}$ meter and $1$ zeptometer $={10}^{-21}$ meter