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i) it is inclined at 30 degrees to the horizontal,

ii) reaches the vertical.

oh no!! I don't have a clue of how to figure out this problem....

2.) A flywheel with an axis 1.0m in diameter is mounted in frictionless bearings set in motion by applying a steadsy tension of 2N to a thin thread wound tightly round the axle. The moment of inertia of the system about its axis of rotation is 5.0 x10^-4 kgm^2. Calculate

i) the angular accleration of the flywheel when 1m of thread has been pulled off the axle,

ii) the constant retarding couple which must then be applied to bring the flywheel to rest in one complete turn, the tension in the thread having been completely removed.

For i), I set: Tr = I alpha, where T is the tension, and r is the radius of axis

2 x 0.5 x 10^-2 = 5 x10^-4 alpha

angular accleration = 20 rad/s^2

ummm....it is correct, but I haven't considered the length of thread being "1m", so what should I do if 2m of thread has been pulled off the axle. Is the answer the same?

For ii), I know that for calculating couple, the equation is force x distance, i.e. 2 x 0.5 x10^-2....but it just doesn't make sense in this question