A stone was thrown from the tower in a horizontal direction with an initial speed of 12 m / s

A stone was thrown from the tower in a horizontal direction with an initial speed of 12 m / s. The speed of the stone in 2s after the beginning of the movement is equal to?

Ignoring the force of air resistance, the movement of the stone horizontally is uniform, and vertically – uniformly accelerated, with the acceleration of gravity g = 9.8 m / s2 directed vertically downward.

Components of the speed of the stone through the time t = 2 s after the start of the movement:

V1x = V0 = 12 m / s;

where V0 is the initial speed;

V1у = gt = 9.8 × 2 = 19.6 m / s;

whence the total speed of the stone in time t = 2 s:

V1 = (V1x ^ 2 + V1y ^ 2) ^ 1/2 = (12 ^ 2 + 19.6 ^ 2) ^ 1/2 = 22.98 m / s.

Answer: 22.98 m / s.