We are given that: Height of tower (h) = 125 m
Initial velocity (u) = 0
g = 10 m/s2
(1) From 2nd equation of motion
For downward motion: h = ut + \(\frac{1}{2}\)gt2
⇒ 125 = 0 x t + \(\frac{1}{2}\) x 10 x t2 = 125 = 5t2
⇒ t2 = 25
⇒ t = 5sec2
(2) From 1st equation of motion,
v = u + gt
⇒ u = 0 + 10 x 5
⇒ v = 50 m/s