An electric-generator turbine spins at 3460.0 rpm. Friction is so small that it takes the turbine 14.9 min to coast to a stop. How many revolutions does it make while stopping? (Do not include a unit with your answer.)
rev/min * 1min/60sec = rev/sec
T (period) = 1/(rev/sec)
w (omega) = 2pi/T
wf = wi + at/r *delta t where at is tangential acceleration and r is radius
The Attempt at a Solution
346.0rev/min * 1min/60sec = 57.66 rev/sec
T = 1/57.66 = 0.0173 seconds
w = 2pi/T = 2pi/0.0173 sec = 363 rad/sec
So I did all the above, but to solve for tangential acceleration I need a radius, which is not given in the question. Once I find tangential acceleration, I can substitute it into the following equation:
Theta final = Theta initial + wi * delta t + ar/2r (delta t ^2)
and theta final can be converted into the number of revolutions.
This is a non-uniform circular motion question.
Please help :)