The ball was thrown vertically upward at a speed of 15 m / s. what movement will he make in 2 s?

At the top of the ball trajectory V = 0:

V = V0 – gt = 0,

where V0 is the initial speed of the ball, V0 = 15 m / s;

g – acceleration due to gravity, g = 9.8 m / s2.

Ball lifting time: t1 = V0 / g = 15 / 9.8 = 1.53 s.

Maximum lifting height of the ball:

h1 = V0 t1 – gt1 ^ 2/2 = 15 × 1.53 – 9.8 × 1.53 ^ 2/2 = 11.48 m.

Ball drop time: t2 = t – t1 = 2 – 1.53 = 0.47 s.

Lowering the ball in time t2:

h2 = gt2 ^ 2/2 = 9.8 × 0.47 ^ 2/2 = 1.08 m.

Ball movement in time t = 2 s:

s = h1 + h2 = 11.48 + 1.08 = 12.56 m.