Answer:
The velocity after 5 seconds is 49.05
Explanation:
Comment
This is an application question for a = (vf - vi)/t
a is the acceleration 9.81 m/s^2
vi is the starting speed ( of zero because the stone is dropped, not thrown).
vf is the final velocity after 8 seconds
t is the time
Solution
9.81 m/s^2 = (vf - vi)/t Substitute the givens
9.81 m/s^2 = (vf - 0)/5 Multiply both sides by 5
9.81 * 5 = 5* vf/5
vf = 49.05