the answer lies in the event of the rotating fluid known as "pressure ugg ultra momentum balance" of the process. we are formed by the rotation of stirring fluid will be maintained at mug among, rather than breaking the mug of the walls, so that the formation of the internal forces of rotating fluid flow of the body should be offset by the pressure gradient. pressure in the center of the minimum cylinder wall to the direction cardy ugg boots of tea gradually increased. think about the rope tied to one end were looted in the movement of the weights, pull the rope to stop the heavy fly. this pull on the rope in the gradient of pressure is equivalent to tea. was stirred, the liquid will be pushed outward to raise the pressure on cylinder wall of tea, while reducing ugg sundance ii the uggs classic ultra pressure on the central location. we can clearly see that, with the rotating liquid was pushed out, in the center of the liquid surface, forming a small whirlpool. in fact, limited by the walls of either tea mug, it will flow out easily sprinkled on the desktop. therefore, all those smaller density than the surrounding liquid floating particles, will ugg shop be the lowest pressure within the mug towards the central movement. this indicates a problem, but there are also inward movement of objects heavier. try to put some peanuts in the tea and even the ugg sundance sale gravel (remember when do not use your best china to do experiments, but even if you are thirsty again placed in the water after the gravel is best drink), you will find peanuts meters or gravel, when you stir tea is still converged to the center.