Standard Form

Very often, we prefer to express the physical quantities that are very large or very small in the standard form.
In standard form, the number are written as,
a * 10n,
where 1 ≤ a < 10 and n is an integer.

For example:

12300000 m = 1.23 * 107 m as the decimal point has been moved 7 places to the left to get the number to be 1.23.

0.0000123 m = 1.23 * 10-5 m as the decimal point has been moved 5 places to the right to get the number to be 1.23.
Excel@Physics