Answer :

sanjna
a = F/m
a = 9/18
a = 1/2
thus the acceleration is 0.5 m/s2
We know, force(f) = (mass×acceleration) = (m×a) N. ...(1)
Here, f = 9 N
        m = 18 kg.                                                                                                 Since, f = m×a.
Therefore, a = f ÷ m = 9 ÷ 18 = 0.5 m/s².
Ans. Required acceleration = 0.5 m/s².