Max Range of a Cannon with Muzzle Speed 322 m/s

[huybinhs]

Homework Statement

On level ground, what is the maximum range (in m) of a cannon with muzzle speed 322 m/s?

Please take a look at this:

http://i995.photobucket.com/albums/af79/huybinhs/cannon2.gif

Homework Equations

R = (V0^2 * sin2angles)/g

The Attempt at a Solution

I think (not sure) the angles in the pic is 30 degree. And came up with the answer:

R= 9162.55 m, and it is wrong. Please help with direction as well as formula and the final answer.

Thanks so much!

 

[Gib Z]

Umm...unless you were meant to get a protractor and measure the angle, you don't have enough information for the problem. Also, the "direction" of the range is to the right. Were you given ANY other information?

 

[Jebus_Chris]

If an object is launched on a flat surface the maximum range comes when the angle is 45.

 

[Keldon7]

Take another look at your range formula, you're given velocity and you know it's proportional to the sine of 2*angle. For what angle is sine 2*angle a maximum?

 

[huybinhs]

Umm...unless you were meant to get a protractor and measure the angle, you don't have enough information for the problem. Also, the "direction" of the range is to the right. Were you given ANY other information?

Please click on the link given. That's all I got!

Again:

http://i995.photobucket.com/albums/af79/huybinhs/cannon2.gif

 

[huybinhs]

If an object is launched on a flat surface the maximum range comes when the angle is 45.

So you mean after looking at the pic link, and you think the angle is 45 degree?

 

[Jebus_Chris]

Does it look like the picture is drawn to scale?

 

[Keldon7]

In all fairness, even if it was scaled up the angle would remain identical, similar triangles and such. But, I don't think they're putting emphasis on the picture here, the question is simply "What is the maximum range for a cannon with muzzle velocity 322m/s?". So Jebus_Chris is right.

 

[huybinhs]

In all fairness, even if it was scaled up the angle would remain identical, similar triangles and such. But, I don't think they're putting emphasis on the picture here, the question is simply "What is the maximum range for a cannon with muzzle velocity 322m/s?". So Jebus_Chris is right.

So, how to resolve this problem? Please help!

 

[Jebus_Chris]

If an object is launched on a flat surface the maximum range comes when the angle is 45.

 

[huybinhs]

If an object is launched on a flat surface the maximum range comes when the angle is 45.

So It comes out with:

R = (V0^2 * sin2angles)/g

=> R = 10580 m. Is this correct?

 

[huybinhs]

So It comes out with:

R = (V0^2 * sin2angles)/g

=> R = 10580 m. Is this correct?

I got it right. Thanks so much for your help ;) Please help me to complete the "Calculate the time it took the marble to travel from N to P" problem ;)