Which load is caused by an object falling from a height and delivering kinetic energy upon impact?

• A. Impact Load
• B. Blast Impact Load
• C. Free-Fall Impact Load
• D. Machinery Impact Load

Answer: (C)

When gravity pulls a body downward, it accelerates and converts its height into kinetic energy. When that object strikes a surface, the kinetic energy is released in a very short time, producing a sudden, high reaction force on the structure. This scenario is described as a free-fall impact load: the load generated by a falling object delivering kinetic energy on impact, with impact velocity determined by height (v = sqrt(2gh)) and impact energy roughly mgh. This helps explain why the load is dynamic and potentially much larger than the object’s static weight, especially if the stopping distance is small. Other terms refer to different sources of impact: blast impact load comes from an explosion, not gravity-driven fall; machinery impact load arises from moving machine parts or rapid deceleration not from a freely falling object.