How long did the body fall from a height of 250 m? What speed did it have at the end of the path?

Task data: h (height from which the fall began) = 250 m; we consider the fall free.

Constants: g (acceleration due to gravity) ≈ 10 m / s2.

1) The duration of the fall: S = h = a * t2 / 2 = g * t ^ 2/2, whence we express: t = √ (2 * h / g) = √ (2 * 250/10) = 7.07 s …

2) Speed at the end of the path: V = a * t = g * t = 10 * 7.07 = 70.7 m / s.

Check: h = V ^ 2 / 2a = V ^ 2 / 2g = 70.7 ^ 2 / (2 * 10) ≈ 250 m (correct).

Answer: The body fell within 7.07 s and at the end of the path reached a speed of 70.7 m / s.