Green is Good

  • Mines
The times they are a-changin’.

This post seems to be older than 14 years—a long time on the internet. It might be outdated.

Nothing like getting the answer right on CAPA your first try. Bonus points (and maybe a prize if I can find one) for the first person to come up with the correct answer to within 3 sig figs. Assume gravity to be 9.81m/s2:
CAPA problem

A block of mass 1.46 kg is attached to a string that is wrapped around a pulley and then attached on the other side to a spring as shown. The pulley is a solid cylinder of mass mp=2.23 kg and radius R=0.4 m (I=(1/2)mpR2). At first the block is held so the spring is unstretched. You then let the block go. What is the speed of the block after it has fallen a distance 0.44 m if the spring’s constant equals 19.5 N/m?