A flywheel 1.2 m in diameter is uniformly accelerated from rest and revolves completely 68 times in reaching a speed of 125 rev/min. Find the time taken to reach this speed(adsbygoogle = window.adsbygoogle || []).push({});

i have been given the correct answer as 65.29 seconds

Wht i have up to now

ω1 = 0

ω2 = 125 r/min = 125/60 = 2.083 r/s

theta = 68*2∏ = 427.26 rads

t = ?

I have tried to use theta = ((ω1+ω2)*t)/2 rearranged to get t = 2theta/ω1+ω2 however my answer doesnt come close

Any suggestions would be appreciated

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# Homework Help: Rotational kinematics help

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