The horizontal distance traveled by the ball (range of motion) is given by the following equation:
![x= v_{0x} t](https://tex.z-dn.net/?f=x%3D%20v_%7B0x%7D%20t)
In which
![x](https://tex.z-dn.net/?f=x)
is the range of motion,
![v_{0x}](https://tex.z-dn.net/?f=%20v_%7B0x%7D%20)
is the horizontal component of the initial velocity, and
![t](https://tex.z-dn.net/?f=t)
is the time of motion.
First, lets calculate the horizontal component of the initial velocity:
![v_{0x}= v_{0}cos( \alpha)=13.9cos(35)=11.39](https://tex.z-dn.net/?f=%20v_%7B0x%7D%3D%20v_%7B0%7Dcos%28%20%5Calpha%29%3D13.9cos%2835%29%3D11.39)
Now, we calculate the time of motion from the equation that described the motion of the ball in the vertical axis:
![y= \frac{1}{2}at^2+ v_{0y}t](https://tex.z-dn.net/?f=y%3D%20%5Cfrac%7B1%7D%7B2%7Dat%5E2%2B%20v_%7B0y%7Dt%20%20)
In which
![y](https://tex.z-dn.net/?f=y)
is the position of the ball vertically,
![v_{0y}](https://tex.z-dn.net/?f=%20v_%7B0y%7D%20)
is the vertical component of the initial velocity,
![a](https://tex.z-dn.net/?f=a)
is the acceleration in the vertical axis (which is gravity), and
![t](https://tex.z-dn.net/?f=t)
is time of motion.
We want to find the time when the ball lands, hence, when
![y=0](https://tex.z-dn.net/?f=y%3D0)
; so the equation becomes:
![0= \frac{1}{2}at^2+ v_{0y}t=\frac{1}{2}at^2+ v_{0}sin( \alpha )t=\frac{1}{2}(-9.8)t^2+ 13.9sin(35 )t](https://tex.z-dn.net/?f=0%3D%20%5Cfrac%7B1%7D%7B2%7Dat%5E2%2B%20v_%7B0y%7Dt%3D%5Cfrac%7B1%7D%7B2%7Dat%5E2%2B%20v_%7B0%7Dsin%28%20%5Calpha%20%29t%3D%5Cfrac%7B1%7D%7B2%7D%28-9.8%29t%5E2%2B%2013.9sin%2835%20%29t)
We rewrite it a bit more:
![-4.9t^2+7.97t=0](https://tex.z-dn.net/?f=-4.9t%5E2%2B7.97t%3D0)
This is a quadratic equation, so we use the quadratic equation formula to solve for time (we'll get two answers):
![t= -\frac{1}{9.8} [{-7.97}+-\sqrt{(7.97)^2}]](https://tex.z-dn.net/?f=t%3D%20%20-%5Cfrac%7B1%7D%7B9.8%7D%20%5B%7B-7.97%7D%2B-%5Csqrt%7B%287.97%29%5E2%7D%5D)
Clearly, one of the answers is
![t=0](https://tex.z-dn.net/?f=t%3D0)
, this is before you kick the ball (it is on the ground), we want the nonzero answer (when it lands) so:
![t= -\frac{1}{9.8} ({-7.97}-7.97})=1.63](https://tex.z-dn.net/?f=t%3D%20-%5Cfrac%7B1%7D%7B9.8%7D%20%28%7B-7.97%7D-7.97%7D%29%3D1.63)
Now, we plug-in the time value to the equation of the motion's range:
The ball will travel 18.57 meters.