A small cannon (angle manipulative) produces an unknown force on a bullet. Simultaneously, a plate is dropped from h`1 . The cannon is d`x away from the target's horizontal location. What angle is needed, as well as the minum velocity, for the bullet to hit the falling target before its impact with the floor h`1 below. this is similar to this animation: http://www.glenbrook.k12.il.us/gbssci/phys/mmedia/vectors/mz.gif [Broken](adsbygoogle = window.adsbygoogle || []).push({});

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I am told that i have to do this "algebraically", using ONLY the 5 kinematic equations (and their projectile equivalent) in order to prove the launch angle. You can only use dx, dy, and h in these equations (and i am guessing variables such as g are also allowed).

I am not sure what is meant by algebraically (specifically); although my method seems awkwardly long, yet i am guessing it would work.

firstly, i calculated the time needed for the object falling vertically to fall (square root: 2h/g = t). I used that equation along with vx = dx / t, to figure out the minmum horizontal velocity. v2x = v1x.

dy = v1y(t) + 1/2gt^2 .

Method 1:

0 (d2y-d1y = 0) = v1xtanX(t) + 1/2gt^2

Rearrange to solve for angle X.

Method 2:

0 = v1tsinX + 1/2gt^2

Rearrange for X.

Im not really sure about this. Im in deep fatigue and cant think correctly. Anyone willing to help out?

Thank you.

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# Homework Help: Projectile Motion Lab Question

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