Answer:
-39.2m/s
Step-by-step explanation:
Given that :
t = 4secs
g = -9.8m/s^2
v = ?
u = 0m/s ( since it was at rest )
V = u +at............. 1
Where v is the final velocity
a = -g = -9.8m/s^2 since the ball was dropped from a height which will eventually make it move against gravity
t = 4secs
Substitute the values into 1
v = 0 - 9.8×4
v = -39.2m/s