I don't totally disagree with Denker and others who want to say that
"radians" are units, but dimensionless units, but it sure causes problems
for students who are trying to do dimensional analysis.
For example, if the angular velocity (w) of a rotating disk is given as 6.28
radians per second, then you can calculate the frequency (f) of rotation by
w/2pi. But what shall we do with the units? It looks to students like the
frequency ought to be 1.00 radian per second. If we want it to be 1.00
reciprocal second (or 1.00 Hz), how do we "get rid of" the radians? I know
there are games we can play to do it... but it confuses the students.
I would rather say that the angular velocity is 6.28 reciprocal seconds and
the frequency is 1.00 reciprocal second (or Hz). That is, I just like to
leave the word "radian" completely out of the discussion.
Michael D. Edmiston, Ph.D. Phone/voice-mail: 419-358-3270
Professor of Chemistry & Physics FAX: 419-358-3323
Chairman, Science Department E-Mail edmiston@bluffton.edu
Bluffton College
280 West College Avenue
Bluffton, OH 45817