Using the rotational equivalent of force:
Which is T = I*Alpha
Where: T is torque, I is the moment of inertia and Alpha is the angular acceleration.
This is for the flywheel: J = 1/2mr^2 = 5*3^2 = 45 kgm^2
From the equation:
T = J*dω/dt
we get:
Δt = J*Δω/T = 45*8.13/110.0 = 3.326 sec