Summarize why a scientist measuring the diameter of an atom or the distance to the moon would use scientific notation

A scientist measuring the diameter of an atom or the distance to the moon would use scientific notation because the diameter of the atom is very small and it would be difficult to write out the value in full. Also, the distance to the moon is a large value hence it can conveniently be written in  scientific notation.

Scientific notation provides a convenient system of writing very large or very small numbers.

Many scientific values are either very large or very small. This posses problems when writing such value. However, the bulk of figures involved in such very large or very small values can be reduced by writing it in scientific notation.

Therefore, the diameter of an atom or the distance to the moon can be written in scientific notation because they involve very small and very large values respectively.

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A scientist using ordinary decimal notation would have to write the diameter of, say, a helium atom as 0.000 000 000 062 m and the distance to the moon as 340 000 000 m.

It is inconvenient, tedious, and cumbersome to write all those zeroes.

It is much easier to write these numbers in scientific notation as 6.2 × 10⁻¹¹ m and 3.4 × 10⁸ m.