Answer :
The magnitude of the angular acceleration of the magnetic disk is determined as 35 rad/s².
Angular acceleration of the disk
The angular acceleration of the disk is determined from the principle of conservation of angular momentum as follows;
τ = Iα
where;
α is angular acceleration
I is moment of inertia of the disk
I = 0.5MR²
I = 0.5 x 0.2 x 2²
I = 0.4 kgm²
τ = Iα
α = τ/I
α = (14)/(0.4)
α = 35 rad/s²
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