physics
posted by Anon .
While waiting to board a helicopter, you notice that the rotor's motion changed from 340 rev/min to 265 rev/min in one minute. Assuming that this acceleration remains constant, calculate how much longer (in seconds) it will take for the rotor to stop.

a = dv/dt = (265340)/60 = 1.25 rev/sec
v = Vi + a t
0 = 265  1.25 t
t = 212 seconds
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