Answer:
The answer is 49m/s.
Step-by-step explanation:
Given,
acceleration (a) =9.8m/s^2
initial velocity (u)=0 (as it was in rest condition in helicopter)
time (t) =5 s
now, final velocity (v) after 5s =?
we have,


or, v = 49m/s
Therefore, the velocity after 5s is 49m/s.
Hope it helps..