Aesthetic engineers are trying to determine what speed should their fountains release water at. For beauty purposes, they would like the water to to be released at an angle of elevation of [math]\theta=30^{\circ}[/math], and for the trajectory to hit the point [math](20,0)[/math]. The water is to be released at a height of [math]5\ \text{m}[/math] away from the ground.
Recall that the equation for projectile motion is given by[br][center][br][math]y=ax^2+bx+c,[/math][br][/center]where [math]a=-\frac{g}{2v^2\left(\cos\theta\right)^2}[/math], [math]b=\tan\theta[/math], and [math]c=y_0[/math]. Create a Geogebra applet to determine the suitable value of [math]v[/math]. Press ENTER after each input.[br][list=1][*]v_0 = Slider(0, 20, 0.1)[/*][*]g = 9.81[/*][*]a = (2 * g) / (3 * (v_0)^2)[/*][*]b = 1 / sqrt(3)[/*][*]c = 20[/*][*]y = a*x^2 + b*x + c[/*][/list]
[math]v\approx12.6[/math]