Mass

Mass is the amount of matter in an object.The SI unit of mass is the kilogram (kg).The mass of smaller objects is described in terms ofgrams (1 kilogram , 1,000 grams). The amount of inertia an object has depends on its mass.The greater the mass of an object, the greater its inertia.

Vector

Vector, is a concept characterized by a magnitude and a direction. A vector can be thought of as an arrow in space drawn from an initial point A pointing to a terminal point B.

Scalar

Scalar is a simple physical quantity that does not depend on direction, and is therefore not changed by coordinate system rotations (in Newtonian mechanics).

Distance

Distance is a numerical description of how far apart objects are at any given moment in time. Distance may refer to a physical length, a period of time, or an estimation based on other criteria (e.g. "two counties over").In most cases there is symmetry and "distance from A to B" is interchangable with "distance between A and B".

Displacement

The vector quantity of distance. It is known as the shortest distance along a single line from the beginning to the end. It depends only on the initial and the final positions.

In the above figure, the initial and the final positions are given by x1 and x2, respectively. The actual path taken by the body is illustrated in blue.The red line shows the displacement. As, show, it is the shortest path between the initial and final positions.

Velocity

Velocity is defined as the rate of change of displacement or the rate of displacement. It is a vector physical quantity, both speed and direction are required to define it. In the SI (metric) system, it is measured in meters per second (m/s). The scalar absolute value (magnitude) of velocity is speed. For example, "5 metres per second" is a speed and not a vector, whereas "5 metres per second east" is a vector. The average velocity (v) of an object moving a displacement (s) in a straight line during a time interval (t) is described by the formula:

velocity(v)= displacement (s) / time(t)

Acceleration

The acceleration of the body is proportional to the vector sum of all forces acting on it (known as net force or resultant force). Acceleration is defined as the rate of change of velocity, or, equivalently, as the second derivative of displacement. It is thus a vector quantity with dimension length/time². In SI units, acceleration is measured in metres/second² (m·s-²). The term "acceleration" generally refers to the change in instantaneous velocity.

acceleration(a)=velocity(v) / time

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