Chapter Summary

PREVIEW

In this chapter the concepts of displacement, velocity, and acceleration are applied to motion in two dimensions. You will learn to describe motion along a curved line, such as a car moving on a race track, a ball flying through the air, or a spacecraft in deep space. The kinematic equations for displacement, velocity, and acceleration developed in Chapter 2 will be applied here to describe projectile motion and relative velocity.

QUICK REFERENCE

Important Terms

Projectile Motion An object moving in two dimensions which experiences only the acceleration due to gravity. Air resistance is assumed to be negligible and there is no acceleration in the x direction, i.e., a_x = 0. In the y direction on earth we have a_y = - 9.80 m/s². A baseball or football thrown from one person to another is a good example. Relative Velocity The velocity of a moving object can take on different values depending on the point of view of the observer. That is, the value of the velocity must be measured 'relative' to a particular observer.

Kinematic Equations for Two Dimensional Motion (Constant Acceleration)