Final answer:
Tensional stresses commonly cause normal faults where the hanging wall moves downward, often occurring at divergent plate boundaries or rift zones.
Step-by-step explanation:
Tensional stresses commonly cause normal faults, where the crust is extended and the hanging wall block moves downward in relation to the footwall block. This type of stress occurs at divergent plate boundaries or rift zones, where the lithosphere is being pulled apart. Normal faults are one of the two main types of dip-slip faults, the other being reverse faults, which are caused by compressional stresses.
In a normal fault, the hanging wall drops down relative to the footwall, which can be seen in places where tectonic plates are moving away from each other, leading to the extension and thinning of the crust.