Canon shooting area in polar coordinates

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Homework Statement


hi,guys.
The directions of shooting e=cos[itex]\alpha[/itex]cos[itex]\varphi[/itex]i+cos[itex]\alpha[/itex]sin[itex]\varphi[/itex]j+sin[itex]\alpha[/itex]k
0<[itex]\varphi[/itex]<=2π;[itex]\varphi[/itex] -horizontally
[itex]\alpha[/itex][0,π];[itex]\alpha[/itex] is vertically
initial speed=v0

I need to calculate the surface equation of canon shots (where it hits).
In other words equations of the surface which is made from canon hits.

Homework Equations


The Attempt at a Solution



My view is that i need to gain horizontal and vertical distance (r),and then i can get the desired equation.

So horizontal distance is r=t|vxy|=tv0|ex+ey|=tv0(cos[itex]\alpha[/itex]cos[itex]\varphi[/itex]i+cos[itex]\alpha[/itex]sin[itex]\varphi[/itex]j)1/2=tv0cos([itex]\alpha[/itex])

So now i need height or in other words the distance in vertical direction(z -direction) or all together?.. I have hard time recalling use of equations of motion.
some help,please?
 
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Is there a question in the problem statement ?
You'll find equations of motion here, or otherwise ##\vec F = m\vec a## is a good one too.

List what you need under 2 and use less shorthand than in
So horizontal distance is r=t|vxy|=tv0|e_x+e_y|=tv0(cos[itex]\alpha[/itex]cos[itex]\varphi[/itex]i+cos[itex]\alpha[/itex]sin[itex]\varphi[/itex]j)1/2=tv0cos([itex]\alpha[/itex])
 
BvU said:
Is there a question in the problem statement ?
You'll find equations of motion here, or otherwise ##\vec F = m\vec a## is a good one too.

List what you need under 2 and use less shorthand than in

Im sorry,i edited the original post,tried to be more specific.
 
Let me try to translate: you want to calculate where a cannon ball lands that is shot from a cannon that is placed on the x-y plane in an empty flatland with no atmosphere, and gravity acceleration g in the -z direction, as a function of ##\phi, \theta## v0 and g.
That right ? Something like http://www.rabidgeek.net/physics-applets/projectile-motion/ ?

Did you find something useful among the equations of motion? Or here or here ?
 
BvU said:
Let me try to translate: you want to calculate where a cannon ball lands that is shot from a cannon that is placed on the x-y plane
Yes,and the direction of cannon is described by [itex]\vec{e}[/itex]=cos[itex]\alpha[/itex]cos[itex]\varphi[/itex]i+cos[itex]\alpha[/itex]sin[itex]\varphi[/itex]j+sin[itex]\alpha[/itex]k

Because 0<[itex]\varphi[/itex]<2pi and [itex]\alpha[/itex][0,pi].Result is not one spot where it would land,but a surface which I am looking for.

Gravity g=-g[itex]\vec{k}[/itex]

BvU said:
Did you find something useful among the equations of motion? Or here or here ?

Yes,I found something useful,I think I could use dv=vvt-gt2/2