Re: newbie here,, need help with parametrics

• To: mathgroup at smc.vnet.net
• Subject: [mg96509] Re: newbie here,, need help with parametrics
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Sun, 15 Feb 2009 03:20:39 -0500 (EST)
• References: <gn5u3e\$gko\$1@smc.vnet.net>

```Hi,

we love to make high school home-works !

With[{g = 9.81, x = 0, y = 0},
Manipulate[
Block[{tEnd},
tEnd = 2*v*Sin[\[Alpha]]/g;
ParametricPlot[
{x + v Cos [\[Alpha]]*t, y + v Sin [\[Alpha]]*t - g*t^2/2}, {t, 0,
tEnd}]], {{v, 20, "Speed"}, 0, 50}, {{\[Alpha], Pi/4, "Angle"},
0, Pi/2}]
]

Regards
Jens

R.J. wrote:
> I am using Mathematica and i'd rather be using derive,,,,, but anyways,,  heres the problem i have to do, a baseball is thrown from the stands 32 feet from the ground at an angle of 30 degrees above the horizontal, initial velocity is 32 feet per second.
>
> what i want to do is find how to plot this in mathematica,, the graph i keep getting says it hits the ground after .8 seconds,   and i know thats not right,,, here is the formula i am using
>
> r = (x + v Cos a) t) i + (y + (v Sin a) t - 1/2 gt^2) j
>
> where x is the initial x position and y is the initial height, v is the initial velocity a is the angle (30*) t is time and g is the gravitational constant..
>
> i'm stuck,,, any help?
>

```

• Prev by Date: Re: Log[]//TraditionalForm
• Next by Date: Re: Re: Typesetting bug
• Previous by thread: Re: newbie here,, need help with parametrics
• Next by thread: Re: newbie here,, need help with parametrics