Explanation:
Given :
Initial angular velocity =w_i= 215 rev/min
Final angular velocity =w_f= 0
Number of revolutions=n =75.0 rev
Using relation
[tex]w_f^2-w_i^2=2\alpha n[/tex]
[tex]0-215^2=2\times 75\alpha[/tex]
[tex]-308.1666 rev/min^2=\alpha[/tex]
Converting to rad/s^2
[tex]\alpha =-1.45 rad/s^2[/tex]
