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.
The scraping and plucking of glacial erosion creates a number of distinct landforms and features. If the glacier erodes into a mountain, it can create a cirque, which is a round hollow with steep sides. It's as if the glacier scoops out the side of the mountain like an ice cream scooper.