Determine the speed of block G, if the block Z is moving up with a velocity of 20 ft/s. The mass of the cord can be assumed negligible. 1) 15 ft/s 

There is one cord in this system having segments which are changing length. Position coordinates S_{G} and S_{Z} will be used since each is measured from a fixed point (C or D) and extends along each block's path of motion. S_{Z} is directed to point E since motion of Z and E is the same. So the total length of the cord at any time is L = S_{G}+ 3S_{Z},
neglecting the arc distance on the pulley because it remains constant. So, the velocity of block G, V_{G} = 20 ft/s (down). . 