What Are the Two Angles to Fire a Shell to Hit a Target 1000m Away?

[Awsom Guy]

Homework Statement

A shell is fired with a muzzle velocity of 350ms/s at a target 1000m away. Calculate two angles at which the shell can be fired .

Homework Equations

I think these equations might help...
v=u+at
s=ut+1/2at^2
v^2=u^2 + 2as
Hope these eqations are right.

The Attempt at a Solution

I thought about maybe this way:
cos(theta)=...
Sorry that is as far as I can go...
Thanks for any help.

 

[tiny-tim]

Hi Awsom Guy!

(have a theta: θ and try using the X² tag just above the Reply box )

Yes, those three equations will solve any constant acceleration problem.

The trick in this case is to write two lots of equations, one for the horizontal components of velocity (with a = 0), and one for the vertical (with a = -g).

Call the time taken "t", and the launch angle θ, and get two simultaneous equations from which you can eliminate t to find θ.

 

[Awsom Guy]

Ok I will try...