[SOLVED] Force with kinetic energy question A 2.5-g bullet traveling at 350 m/s hits a tree and slows uniformly to a stop while penetrating a distance of 12 cm into the tree's truck. What force was exerted on the bullet in bringing it to a rest? Not sure on this one. I know to find to the kinetic energy would be KE=1/2mv^2. I'm not sure if that is needed though. And to find force would be F=W/D or F=MA. So far I only have KE=153.125 using the equation above. I plugged in 1/2(.0025kg)(350m/sec)^2. Now I'm not sure what to do. I want to try to find W since it includes distance. I don't know if there is an equation to find work by using only M,V,and X. Hmm..I'm confused now.