1. The problem statement, all variables and given/known data A shell of mass m and speed v explodes into two identical fragments. If the shell was moving horizontally (the positive x direction) with respect to Earth, and one of the fragments is subsequently moving vertically with speed v, find the velocity v of the other fragment immediately following the explosion. (Use the following as necessary: v.) 2. Relevant equations conservation of momentum: m1iv1i= 0.5m1fv1f+0.5m2fv2f 3. The attempt at a solution So, what I did was set mv=.5mv+.5mv. Solving for v, I get v=v. I don't know what I'm doing wrong here. I'm pretty sure I'm supposed to be using the conservation of momentum equation, but I don't know where I'm going wrong. Thanks in advance for any help!