Solution :
Given data :
Mass of the merry-go-round, m= 1640 kg
Radius of the merry-go-round, r = 7.50 m
Angular speed, [tex]$\omega = \frac{1}{8}$[/tex] Â rev/sec
               [tex]$=\frac{2 \pi \times 7.5}{8}$[/tex]  rad/sec
               = 5.89 rad/sec
Therefore, force required,
[tex]$F=m.\omega^2.r$[/tex]
  [tex]$=1640 \times (5.89)^2 \times 7.5[/tex] Â
  = 427126.9 N
Thus, the net work done for the acceleration is given by :
W = F x r
  = 427126.9 x 7.5
  = 3,203,451.75 J