## Ballistics formula(how to solve for speed?)

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standardtoaster
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### Ballistics formula(how to solve for speed?)

Hello, I really appreciate your site and all of the help that you do here. I am pretty sure that this section was the best choice for my problem. I use an application called Algodoo to make and use mathematical formulas. I use Algodoo to do this because I'm able to see the formula at work and because it has the only scripting language I am very fluent with.

I want to be able to find out how fast an object should be shot given the angle it is shot from and the point at which it will hit. How would I go about doing this? Here's what I have looked at so far: http://www.jqjacobs.net/astro/arc_form.html#formula The velocity of an object in Algodoo is in X and Y values.

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```Angle = 45° Velocity = [?, ?] m/s Point it will hit = [0, 10] ```
I hope that you can understand what I wrote. I tried my best to describe it in as much detail as possible. I thank you for any help that you will give me.
Last edited by standardtoaster on Sun Nov 22, 2009 7:10 pm, edited 3 times in total.

stapel_eliz
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There are many different models for projectile motion ("ballistics"). The model you would need would depend upon the inputs and assumptions. For instance, are you taking air resistance, gravity, etc, into account?

Please reply with the full and exact text of the exercise, along with the complete instructions and any formulas or algorithms that you think you may be expected to apply to this homework problem.

Thank you!

standardtoaster
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### Re: Point object hits based on angle and velocity

This isn't for homework, this is just for fun! I also realized that what I stated in the original post was not what I had originally meant. I will update the original post as soon as possible. Here's what I'm trying to find out: given the angle at which the object is shot and given the point at which the object should hit, what should the velocity of the object be? Yes, I am taking gravity into account but not air resistance. Algodoo does not have air resistance yet but it does have air friction. Instead of air resistance I will be taking air friction into account instead. I think that this is what I mean: Given the angle the object is shot at and the point that it should hit how fast should the object be shot?

standardtoaster
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### Ballistics formula(how to solve for speed?)

Sorry for the double post but I found out what the name of the formula is. It is the ballistics formula.