Physics p4 help m/j 2008 qn 1 (b)

[gentleman]

i did the following:
d = 0.35
0.72 W = mdω^2
0.72 x 9.81 x m = m x 0.35 x ω^2
ω^2 = (0.72 x 9.81) / (0.35)
ω = √(0.72 x 9.81) / (0.35)
ω = 4.49
now i have a doubt to find , the no. of revolutions per minute ?
HELP ME =)

 

[gentleman]

HEEEY I GOT IT . SORRY !!!