Click the LEFT mouse button in gray block and drag the object to some other place. Numbers shown in the upper left pairs are the X coordinate and the width of the object. Number shown in the upper right pairs are the Y coordinate and the height of the object. The mass of the object is shown in the textfield. You can drag the object and let it submerged in the fluid.
Black vector represents the weight of the object.
Black circle is the center of gravity . Red vector represent the buoyant force . The animation starts when you release the object. Blue curve is the displacement in y-direction of the object verses time. Red curve shows the velocity of the object as a function of time.