A ball was thrown from the tower in a horizontal direction, and after 2 seconds it fell into the water at a distance of 30 m

A ball was thrown from the tower in a horizontal direction, and after 2 seconds it fell into the water at a distance of 30 m from the base of the tower. What is the speed of the ball when it touches the water?

The horizontal movement of the ball is uniform, and the vertical movement is uniformly accelerated, with an acceleration g = 10 m / s2 directed vertically downward.
Ball motion equation:
H = gt ^ 2/2,
where H is the initial height of the ball, m; t is the flight time of the ball, t = 2 s.
H = 10 × 2 ^ 2/2 = 20 m.
Ball flight range L:
L = V0 t,
whence the initial velocity V0:
V0 = L / t = 30/2 = 15 m / s.
Ball speed at the moment of contact with water:
V1x = V0 = 15 m / s;
V1у = gt = 10 × 2 = 20 m / s;
V1 = (V1x ^ 2 + V1y ^ 2) ^ 1/2 = (15 ^ 2 + 20 ^ 2) ^ 1/2 = 25 m / s.