Basically, a passive radiator is a reactionary device as the name suggests. When a driver (such as a subwoofer) is mounted to a sealed speaker box (enclosure), the physical forward/back movement of the speaker affects the internal air pressure of the enclosure.
The 3 landforms created by wave erosion sometimes called coastal  erosion are headlands and bays, cliffs and wave cut platforms and  finally caves, arches, stacks and stumps â¦ . Wave erosion is the  wearing away of land and the removal of beach by wave currents.
Landforms From Wave Erosion. 1  Wave-cut cliffs form when waves erode a rocky shoreline. They create a vertical wall of exposed rock layers. 2  Sea arches form when waves erode both sides of a cliff. They create a hole in the cliff. 3  Sea stacks form when waves erode the top of a sea arch. This leaves behind pillars of rock.