Conversion Factor
This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.
State
A conversion factor is a ratio of two equivalent quantities in different units, equal to one, changing a unit without changing value.
Show
Because 1 in. equals 2.54 cm, both 2.54 cm/1 in. and 1 in./2.54 cm are valid factors, each equal to one.
Watch for
Only one orientation of a conversion factor cancels the starting unit — the wrong one produces a nonsense unit.