Motion Drag
The Drag behavior simulates the force of friction on a moving object, slowing it down over time. Applying the Drag behavior is an easy way to decelerate objects with multiple behaviors that create complex motion.
Adjust this behavior using the controls in the Behaviors Inspector:
Affect Subobjects: A checkbox, available when this behavior is applied to an object that contains multiple objects, such as a group, a particle emitter, a replicator, or a text layer. When this checkbox is selected, all objects enclosed in the parent object are affected individually. When this checkbox is deselected, all objects enclosed in the parent object are affected by the behavior together.
Amount: Sliders that slow down an object over time, causing it to eventually come to a stop. Higher Drag values result in the object coming to rest sooner. Click the Amount disclosure triangle to adjust the drag applied to the X, Y, and Z values separately. An example of this is to create a situation where an object’s vertical speed slows down faster than its horizontal speed.
Include X, Y, and Z: Buttons that specify the space that Drag affects. For example, when X and Y are enabled, the object drags in the XY plane; when Y and Z are enabled, the object drags in the YZ plane.