ok im doing a project where i shoot a baseball from an air cannon. i am trying to solve for the muzzle velocity of what i should get at certain pressures. also i used the cross sectional area of the baseball, is that what i should use? when i solved for the force i used the force acting on the baseball from (10 psi of pressure+air pressure)-(air pressure) and once i found the force, i divided by the mass of the baseball and got the acceleration. anyways after using si units and everything i got the final velocity to be 60.79 m/s or 136.7 mph. i know for a fact that is not right. how can i get close to the actual velocity i measured? could i try and figure out the force of friction between leather and pvc and subtract that from my force earlier?