Projects

A Fluid-filled Yo-Yo

    

This is a yo-yo where the sides are clear and filled with fluid. The fluid will be a mixture of colored oil and water. This will demonstrate the fact that oil and water don't mix. When used, the colored beads around the edge of the yo-yo will show that it is moving, but the fluid inside won't move all that much. This is because the friction between the fluid and the side walls is almost neglibile.

This toy is marketed to children ages 6 and up. It is made out of plastic, and both fluids inside are non-toxic. The only danger is with the string, so parental supervision is necessary.