If you are asking about earthquakes, the answer to your question can be easily found in the so called Richter Magnitude Scale. This scale is internationally used to measure the force of an earthquake, and evaluate its outcomes on the environment in terms of damage. So, the earthquake with the power equalling 4 (in fact, up to 4.9) is considered a light earthquake. It is already easy to notice, usually by the rattling sound and smaller objects moving indoors and outdoors; some of them can fall or get knocked over. The damage it does to the environment (buildings, property, and so on) is usually minimal, or even none. It is unlikely that a light earthquake causes destruction.
In its turn, earthquakes with the magnitude of 5 and up to 5.9 are related to the so-called moderate ones; poorly constructed buildings such as shacks in the slums usually suffer the biggest damage, and may even collapse. However, regular concrete buildings suffer only minimal damage - broken windows, for example, and the damage caused by the objects falling indoors. Moderate earthquakes can hardly be unnoticed by someone.