Position vector, the line having one finish fastened to a body and therefore the alternative finish connected to a moving purpose and accustomed describe the position of the purpose relative to the body because the purpose moves, the position vector can modification long or in direction or in each length and direction.
If drawn to some scale, the modification long can signify a modification within the magnitude of the vector, whereas a modification in direction can signify a rotation of the vector.
Changes in magnitude and direction area unit the sole changes that a foothold vector will expertise, and therefore the speed of the purpose is outlined because of the time rate of modification of the position vector.
To some extent moving on a straight path, a foothold vector coinciding with the trail is that the most convenient; the rate of the purpose is adequate to the speed at that the magnitude of the vector changes with relevancy time, and it’ll be a vector lying on the road.
For some extent moving on a circular path, a foothold vector coinciding with a radius of the circle is that the most convenient; the rate of the purpose is adequate to the speed at that the direction of the vector changes with relevancy time, and it’ll be a vector at right angles to the position vector.
To some extent moving on a noncircular curving path, the position vector modifications in each magnitude and direction; the rate of the purpose is that the addition of the 2 rates of change, one a vector on the position vector and therefore the alternative a vector at right angles to that.
Specifying the position of an object is essential in describing motion. In one dimension some typical ways are:
x(t) is used to represent position as a function of time.
In two dimensions, either cartesian or polar coordinates may be used, and the use of unit vectors is common. A position vector r may be expressed in terms of the unit vectors.
Displacement (symbolized d or s ), conjointly referred to as length or distance, maybe a one-dimensional amount representing the separation between 2 outlined points.
The quality unit of displacement within the Systeme International d’ Unites of Units ( SI ) is that the meter (m). Displacement is typically measured or outlined on a line.
In a train, a passenger moves from point B, which is 7m away from its initial position, point A, at 3m, the displacement will be calculated as:
=7m – 3m
Thus, the displacement is equal to 4m(positive). Hence, the passenger is moving forward.