Here; f = 450 rev/ min = 450/60 rev/s
f. = 15/2 rev/s
Therefore the angular velocity w. = 2Ο fβ’
= 15Ο rad / sec at t= 10s, w = 0
Therefore Angular acceleration
a=w-w./t
= w + 1/2 at^2
= 15Ο * 10 - 1/2 (3Ο/2) 10^2
= 150-75m = 75Ο rad
Therefore No. of revolution = β’/2Ο = 75/ 2Ο
= 37.5
