1. The problem statement, all variables and given/known data "a metal wire of diameter .23mm and unstretched length 1.405 is suspended vertically from a fixed point. when a 40n weight was suspended from the lower end of the wire, the wire stretched by an extension of 10.5mm. calculate the work done on the spring." i know the formula for work done on a spring, but i do not understand why it's given by half of the force. the 40n's force is constant, so why do i need to half it? why isn't it just force*distance/40*(10.5*10^-3)??