The units on f are radians. The ratio of the circumference of a circle to its diameter is named by the Greek letter pi. We use it in the upper case to help distinguish it from regular text. The numerical value of PI is approximately 3.1415926. Position The location of an object relative to some point we have chosen to be the reference point.
Position is a vector quantity.
The potential energy of an object is the energy that object has as a result of its position relative to other objects. The numerical value of potential energy depends on the nature of the interaction of the object with its surroundings and the choice of a position to be the zero energy point. A characteristic that is inherently associated with the object which is said to have that property. For example the mass of an object is one of its properties. So also might be color, density and many other characteristics.