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.
Three landforms created by wind are; sand dunes, yardangs (half-teardrop shaped formations hill sized, and deflation hollows (wind swept depressions.
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.