The initial angular speed of the fan will be 55.0 rad/sec. The angular speed of the fan decreases to 84.7 rad/s in 2.96 s.
Angular acceleration is defined as the pace of change of angular velocity with reference to time.
Given data;
Final angular speed,[tex]\rm \omega_f = 84.7 rad/s[/tex]
Initial angular speed, [tex]\rm \omega_i = ?[/tex]
Time period,t= 2.96 s
Angular deceleration = 47.2 rad/s²
[tex]\rm \alpha =\frac{\omega_f-\omega_i}{t} \\\\\rm 47.2 =\frac{84.7-\omega_i}{2.96} \\\\ \omega_i = 55.0 \ rad/sec[/tex]
Hence the initial angular speed of the fan will be 55.0 rad/sec.
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