A 1 complete revolution corresponds to an angular displacement of 2π rad, or 360º. (So there are 180º for every π rad.) Also, there are 60 seconds to 1 minute. So, the angular velocity in rad/s is
(2000 rev/min) * (2π rad/rev) * (1/60 min/s) = 200π/3 rad/s
or approximately 209.44 rad/s.
B First convert the angular velocity to degrees per second (º/s):
(200π/3 rad/s) * (180/π º/rad) = 12,000 º/s
We want to find the time <em>t</em> it would take for the propeller to turn 36º:
36º = (12,000 º/s) <em>t</em>
==> <em>t</em> = 36º / (12,000 º/s) = 3/1000 s
or approximately 0.003 s.