rowlfe
Leverage. In effect, the bow is a lever system, with the arrow the thing being lifted by the lever. The pull is what moves the lever. In your case your effective lever length of the lever is longer, so less pull is needed. Note the distance things move. When you pull back your bow, how far does the string MOVE? How far does the same point on the cross bow move? Your draw may be 2 feet, while the crossbow may only be 4 inches. The end result is the same because both store the same amount of energy in the "spring" you charge by drawing the string back... Force over distance is what applies. If I have a lever tryng to turn a pipe 12 feet long with one pound on the end (your bow), it applies the exact same force (12 foot-pounds) as a lever 1 foot long with 12 poinds on the end (the crossbow). If I put a 2 foot pipe wrench on the pipe these two levers are trying to turn, I need a 6 pound weight to stop the levers from turning the pipe.