How long was the body in free fall if it fell to the ground at a speed of 40 m / s?

To find the required time during which a given body was in free fall, we apply the formula: V = a * t = g * t, whence we express: t = V / g.

Constants and variables: V – speed of a given body at the moment of touching the ground (V = 40 m / s); g – acceleration due to gravity (g ≈ 10 m / s2).

Calculation: t = V / g = 40/10 = 4 s.

Answer: The given body should have been in free fall for 4 seconds.