The inner globe floats in an almost friction free environment, much like the earth iself. This globe has the same average density as the fluid it floats in, so threre is no force or contact between the inner globe at the north and south poles and the inside surface of the outer shell.

The rotation of the globe creates fprces in the fluid that enter the inner ball and prevent contact at the equator, so the inner globe is not actually touching the outer shell. At these low speeds the fluid friction is very low.