Develop concepts of work and energy transformations using this simple apparatus. A favorite in physical science and conceptual physics classes! Kit includes eight 6' lengths of 1" pipe insulation, ten 3/4" wooden balls, ten 3/4" glass balls, ten 3/4" steel balls and two 50 yd rolls clear packing tape. Each 6' length of pipe insulation halves to yield 12' of track materials (recommended for each student group.) Activity included.