As per the question, the initial velocity of a object[u] = 0
The acceleration of the object [tex][a]=4.6\ m/s^2[/tex]
The time [t] = 12.3 s
We are asked to calculate the velocity of the object at that time.
From equation of kinematics we know that-
V = u+at [Where v is the final velocity of the particle]
=0+4.6*12.3 m/s
=56.58 m/s [ans]