Answer:
ωi = 15.4 rev/sec
Step-by-step explanation:
Since the movement of the fan is rotating, we are thus dealing with Rotational motion. In rotational motion, for angular speed to take place also means angular acceleration is also occurring.
angular acceleration = α = (change in speed)/(change in time)
angular acceleration = α = Δw/Δt = (ω - ωi) /(t- t₀) ..........(equation 1)
α = (ω -ωi) /(t- 0)
α = (ω-ωi) /t
ωi = ω - αt ......................................(equation 2)
where ωi is the initial angular speed.
We replace the values for ω, t and α
ωi = 105 rad/sec - ( 4.4 rad/sec² )(1.85s) = 96.86 rad/s = 15.415747788 rev/sec