21 miles per hour in meters per second
Result
The conversion result is: 21 miles per hour is equivalent to 9.38784 meters per second.[1]
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Conversion in the opposite direction
The inverse of the conversion factor is that 1 meter per second is equal to 0.106520775812114 times 21 miles per hour.
It can also be expressed as: 21 miles per hour is equal to 1 / 0.106520775812114 meters per second.
Approximation
An approximate numerical result would be: twenty-one miles per hour is about nine point three nine meters per second, or alternatively, a meter per second is about zero point one one times twenty-one miles per hour.
Footnotes
[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).
Results may contain small errors due to the use of floating point arithmetic.