Example and homework

In a given reference system the position of a particle can be specified by a single vector namely the displacement of the particle relative to the origin of the coordinate system. This called the position vector of the particle . In this lecturer we study the position, velocity and acceleration of a particle.
Position and particle
The position of a particle on an x-axis located the particle with respect to the origin , or zero point , of the axis . the position is either positive or negative , according to which side of the origin the particle is on , or zero if the particle is at the origin.
The positive direction on an axis is the direction of increasing positive number s , the opposite direction is the negative direction. The moving object is either a particle (by which we mean a point – like object such as electron) or an object that moves like a particle such that every portion moves in the same direction and at the same rate.). in our study , we describe the moving object as a particle regardless of its size.