This is the PROBLEM: Flinstone has a problem too. He built a beam mover, described below (on the attachment, DOC file, look down), but can't figure it out. Perhaps you can help. Two identical wheels and axles sets were carved from from logs. In each set, the 50 cm diameter wheels and the 14 cm diameter axle were a single piece of wood. They are used to move a very long wooden beam resting on the axles as shown. If the beam moves 80 cm over the level ground, how far does the center of each wheel move? ANS = 64 cm I know that if the wheel moves one revolution 2pi*D, then the center moves pi*D, but the beam also moves over the axle. I'm not sure if here the beam moves 2pi*d or pi*d. where D is the radius of the wheel and d is the radius of the axle. Any help would be great. Thanks a lot.