1. The problem statement, all variables and given/known data I want to calculate the torque of the construction or the needed Power (Watt) to rotate it. The construction is a tube and on top of tube is stuck a rectangular parallelepiped: Tube: inner diameter=d=92mm, outter diameter=D=102mm, lenght=L=3000mm, mass=12.34kg Rectangular parallelepiped: x=3000mm, y=5000mm, z= 50mm, mass=250kg http://www.ffevents.gr/nikos/sxediopaint.jpg [Broken] ...........Please assume missing data if needed.............. 2. Relevant equations 3. The attempt at a solution I dont know exactly because I am messed. I thought about Moment of Inertia or loads.