21. A common misconception occurs between phase velocity and group velocity ( analogous to centres of mass and gravity ). 22. :: : It is the centre of mass of the object ( this hypothetical rod ) that orbits. 23. As a martial art, I Liq Chuan emphasises control of the opponent's centre of mass .. 24. So the centre of mass of the shreds of the balloon and of the air will move in opposite directions. 25. Examples include the FMR layout, with the centre of mass of the engine between the front axle and the firewall. 26. For some time after the fall of Rome, large circus buildings fell out of use as centres of mass entertainment. 27. Any increment in total kinetic energy is unusable as the Centre of Mass of the system must maintain a constant velocity. 28. Certainly the device IN THE FIRST DIAGRAM will ROTATE about its centre of mass and not move anywhere when transfering the fluid. 29. Satellite ranging has already shown that for Mars, the centre of mass and the geometric centres do not coincided exactly either. 30. The centre of mass of the three particle system thus lies on the internal bisector of " " D ".
