The case where the angular speed of the bar will increase at a fast rate is at smaller radius compared to the initial radius from the center of rotation.
The principle of conservation of angular momentum states that the total angular momentum of a closed system is always conserved.
[tex]I_i \omega _i = I_f \omega _f[/tex]
where;
[tex]\omega _f = \frac{I_i \omega _i }{I_f} \\\\\omega_f = \frac{(1/2MR_i^2)\omega _i}{1/2 MR_f^2}\\\\\omega _f = \frac{R_i^2 \omega _i}{R_f^2}[/tex]
where;
The angular speed of the bar depends of the moment of inertia of the bar which in turn depends on axis of rotation.
Thus, the case where the angular speed of the bar will increase at a fast rate is at smaller radius compared to the initial radius from the center of rotation.
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