Velocity is a vector quantity which refers to "the rate at which an object changes its position." Imagine a person moving MORE
A physical quantity (or "physical magnitude") is a physical property of a phenomenon, body, or substance, that can be quantified by measurement.
The following outline is provided as an overview of and topical guide to physics:
Physics – natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.
Introduction to mathematics of general relativity
In mathematics, physics, and engineering, a Euclidean vector (sometimes called a geometric or spatial vector, or—as here—simply a vector) is a geometric quantity having magnitude (or length) and direction expressed numerically as tuples [ x , y , z ] splitting the entire quantity into its orthogonal-axis components. A vector is an object that is an input for or an output from vector functions according to vector algebra. A Euclidean vector is typically sketched as a directed line segment, or arrow, connecting an initial point A with a terminal point B and denoted by However, as an informational object, the vector is not as informative as a directed line segment (an ordered list of two points [ A , B ]) but rather expresses the displacement, or vector offset (change in location), A --> B. Technically, the [ x, y, z ] components of vector are equal to the vector difference minus . In this way, the vector considered as a numerical quantity conceals the locations of A and B while imparting the location of point B relative to A as if A were the coordinate origin.
Vectors play an important role in physics: velocity and acceleration of a moving object and forces acting on it are all described by vectors. Many other physical quantities can be usefully thought of as vectors. Although most of them do not represent distances (except, for example, position or displacement), their magnitude and direction can be still represented by the length and direction of an arrow. The mathematical representation of a physical vector depends on the coordinate system used to describe it. Other vector-like objects that describe physical quantities and transform in a similar way under changes of the coordinate system include pseudovectors and tensors.
The mathematics of general relativity are very complex. In Newton's theories of motions, an object's length and the rate of passage of time remain constant as it changes speed. As a result, many problems in Newtonian mechanics can be solved with algebra alone. In relativity, on the other hand, length, and the passage of time change as an object's speed approaches the speed of light. The additional variables greatly complicate calculations of an object's motion. As a result, relativity requires the use of vectors, tensors, pseudotensors, curvilinear coordinates and many other complicated mathematical concepts.
All the mathematics discussed in this article were understood before the proposal of Einstein's general theory of relativity.