m = 1000 kg
F = 0,0015 MN = 1500 N = 1500 kg * m/s^2 ; mega = 1000000
V = 9000 dm/min = 9000 * 0,1 m /60 s = 900 m/60 s = 15 m/s
t = ?
F = m * a
a = F / m
a = 1500 kg * m/s^2/1000 kg
a = 1,5 m/s^2
a = V/t
a *t = V
t = V/a
t = 15 m/s /1,5 m/s^2
t = 10 s