Complex sentence: He then devised an experiment in which he magnetically levitated a superconducting rotating disc, and he reported that objects held above the rotating disc underwent a reduction of between 0.5 to 2% in weight.
Split into simpler sentences: He then devised an experiment in which he magnetically levitated a superconducting rotating disc. He reported that objects held above the rotating disc underwent a reduction of between 0.5 to 2% in weight.