The ball is thrown in a horizontal direction at a speed of 10 m / s, and the range of the ball

The ball is thrown in a horizontal direction at a speed of 10 m / s, and the range of the ball is equal to the throwing height. How high is the ball thrown?

Neglecting the air resistance, we find that the horizontal movement of the ball is uniform, and the vertical movement is uniformly accelerated, with an acceleration g = 10 m / s2.

Equation of vertical motion of the ball:

H = g t ^ 2/2,

where H is the initial height of the ball above ground level, m; t is the time the ball falls, s.

Since the horizontal speed of the ball is constant, the distance L is equal to:

L = V0 t, whence t = L / V0.

Throw height: H = g × (L / V0) ^ 2/2 = g × H ^ 2 / (2 V0 ^ 2),

from where H:

H = 2 V0 ^ 2 / g = 2 × 10 ^ 2/10 = 20 m.