Mathematics For Woodworkers
Calculating an Arc
Arc Math (Height, Width, and Radius)
Enter the two measurements of the arc that you know.
Press the title button of the remaining box to compute
the third measurement.
The Formula:
The formula to compute arc measurements is:
2hr = h2 + (w/2)2
where
h = height
w = width
r = radius
Example
To find the radius of an arc that is .75 inches high and 3.5 inches wide:
enter .75 for height
enter 3.5 for width
press Radius button
The answer (2.41667) is computed and displayed
Hints
If you only know one number you can play with the remaining
numbers to work out two that fit.
The box titles are submit buttons  don't look for a special
"submit" or "compute" button. Simply fill in the known values,
then press the button next to the box that represents the value
to be computed.
Credits
Thanks to Joel P. Watson for this javascript calculator, Mary Ann Watson
 Joel's LOML, proofreading Doug Watson  scripts, testing


