Are you smart enough to be an astronaut?

[3catcircus]

Originally Posted by August

The three wheels in the middle seem to be a combination of larger, smaller and the same size as 1 & 2 so my guess would be A. As fast as wheel 1.

Visually and logically, same size wheels should rotate at the same speed when one is the driver and the other is driven by it. What complicates things is not knowing the sizes of the idler wheels, so you have to assume they will result in cancelling each other out or fool yourself into believing that they're going to have different angular speeds - unless you can do the math to prove it to yourself.

Easiest thing to do is to apply the law of gearing and assume each wheel is a gear with a single tooth, and then do the calcs for a compound gear train. Your result should match your gut instinct that both wheels that are the same size will spin at the same speed. But again - to do this you'll need to know the diameters of all the wheels.