Declining estrogen levels can trigger severe pain in the lower lumbar region. The lower back pain due to estrogen deficiency can best be described as excruciating pain which radiates down the buttocks and legs. The incapacitating lower back pain may also hamper every day tasks.
A Position vector is a vector that describes position of a point in space. Often the position of such a point is nothing but the x,y, and z coordinates of the point with origin as the reference point. The direction of such a vector is the arrow or...
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.