The body falls freely from a height of 20s. The initial velocity of the body is zero.

The body falls freely from a height of 20s. The initial velocity of the body is zero. At what height it will be in 2s after the start.

t = 20 s.
t1 = 2 s.
g = 9.8 m / s ^ 2.
Vo = 0 m / s.
h1 -?
Let us find the height H from which the body freely falls with the acceleration of gravity g: H = g * t ^ 2/2.
H = 9.8 m / s ^ 2 * (20 s) ^ 2/2 = 1960 m.
During the time t1 = 2 s, the body will cover the distance: S = g * t1 ^ 2/2.
S = 9.8 m / s ^ 2 * (2 s) ^ 2/2 = 19.6 m.
Let’s find the height of the body h1 2 seconds after the start of the movement by the formula: h1 = H – S.
h1 = 1960 m – 19.6 m = 1940.4 m.
Answer: after 2 s, the body will be at a height of h1 = 1940.4 m.