1. The problem statement, all variables and given/known data A spring gun is loaded with a 500 gram projectile (position is given in centimeters and time is given in seconds) The spring is massless and therefore has no kinetic energy. How much potential energy is converted to kinetic energy when the ball is at -4 cm. Velocity=2.69 cm/s Time=.72 seconds 2. Relevant equations K=1/2 mv squared 3. The attempt at a solution 1/2 (500g)(7.236 cm squared/seconds squared) 3618 grams/cm squared/seconds squared Now I don't know how to set up the conversion to meters and kilograms. Can someone please help? The other question I have is... How much potential energy is converted to kinetic energy in the spring gun? Would the answer be zero because the spring is massless?