Mechanical motion describes how objects change their position over time. In physics, we often model real objects as point particles to simplify our analysis. A point particle is an idealized object that has mass but no size, allowing us to focus on its motion through space.
Mechanical motion can be classified into different types. Linear motion occurs when an object moves along a straight line. Circular motion happens when an object follows a circular path. Oscillatory motion involves repetitive back-and-forth movement around an equilibrium position.
Position tells us where an object is located in space at any given time. Displacement is the vector that points from the initial position to the final position. Unlike the actual path traveled, displacement only depends on the starting and ending points, making it a straight-line vector quantity.
Velocity describes how fast an object changes its position and in which direction. It is defined as the rate of change of position with respect to time. Speed is simply the magnitude of velocity, representing how fast an object moves regardless of direction. While velocity can be negative, speed is always positive.