What exactly is a moment? There are many different definitions for this concept. It can refer to a short time span (in physics), a subjective experience, or even the length of a pause in a conversation. Despite these differing definitions, a moment can be defined as an interval that is asymptotically dense, meaning that every smaller interval is contained within the next one, and that the duration of any given interval is identical to that of the whole.
Scientifically, a moment is a fraction of a minute. In the Middle Ages, a solar hour was defined as 40 moments, which corresponded to around 90 seconds today.
A moment in physics is a product of force and a perpendicular distance to the pivot of an object. The force exerted on a spanner, for example, generates a moment equal to the product of the applied force and the distance from the point of contact to the nut.
Subjectively, a moment can be used to describe a feeling, such as joy or sorrow. These are subjective experiences that can vary widely between individuals, and a particular individual may experience a moment in a very different way than another person.
In physics, moments are also used to calculate work done by a force on an object. A skater, for example, can use the principle of moments to determine how much force she needs to exert to balance a seesaw. The formula for calculating the moment of an object is M=Fd, where F is the applied force and D is the perpendicular distance from the centre of the object to the pivot.