Determine the height from which the body fell, if at the moment of impact on the surface of the earth it had a speed of 30 m / s.

Suppose that before the start of the fall, the body’s velocity v0 was equal to zero.
Let us find the falling time of the body, expressing it from the formula for the speed of uniformly accelerated motion.
g = 9.8 m / s2 – acceleration of gravity;
v = v0 + g * t;
t = v / g = 30 / 9.8 = 3.06 s;
Let’s find the height from which the body fell:
h = g * t ^ 2/2 = 9.8 * 3.06 ^ 2/2 = 45.9 m.
Answer: 45.9 m.