A ball is kicked with an initial velocity of 17 m/s in the horizontal direction and 13 m/s in the vertical direction. (Assume the ball is kicked from the ground.) (a) At what speed (in m/s) does the ball hit the ground

The velocity of the ball before it hits the ground = 21.4m/s

Explanation:

The question can be solved as a projectile problem. One of the main characteristics of the parabolic motion is the symmetry it has as long as the initial height is equal to the final height with respect to a reference system, the vertical displacement of the horizontal displacement being independent. 

The vertical component of velocity is 13m/s

The horizontal component is 17m/s

The ball's pathway is defined by a right angle triangle .

Using Pythagorean

Let vertical component be a

Let horizontal component be b

Let the speed of the ball before hitting the ground be c

Pythagorean is given by:

a^2 + b^2 = c^2

13^2 + 17^2 = c^2

169 + 289 = c^2

458 = c^2

Sqrt(458) = c

21.4 m/s = c