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 09-05-2005, 09:55 PM #5 fabrizio Senior Member   Join Date: Oct 2004 Location: Georgia Posts: 4,835 Another Question I got the first part of this question, but I'm having problems with the second part. 1. A cannon, located 60.0 m from the base of a vertical 25.0m-tall cliff, shoots a 15-kg shell at 43.0 degrees above the horizontal toward the cliff. The first part asks "What must the minimum muzzle velocity be for the shell to clear the top of the cliff?" I got 32.6 m/s, which is correct. However, the second part asks "The ground at the top of the cliff is level, with a constant elevation of 25.0 m above the cannon. Under the conditions of part (a), how far does the shell land past the edge of the cliff?" I got 49.2 m twice, but that is not correct. What's the right answer and how do I do it? I tried breaking up the minimum velocity into x and y components and figuring out the time required for the shell to clear the cliff using the equation (-1/2)(9.80(t ^2) + (v,y)(t) -25.0 = 0. I then multiplied this time by the x component of the minimum velocity and subtracted 60 from my answer. Reply