California Educator Credentialing Examinations (CBEST) English Practice

The scenario that best illustrates an example of acceleration is one where an object changes its velocity, which includes changes in speed or direction. Acceleration is defined as the rate of change of velocity, and can occur even if the speed remains constant, provided there is a change in direction. In the context of the chosen scenario, the bird flying at 35 mph exemplifies acceleration as it moves above a highway, exceeding the slowed traffic. Here, we consider both the speed of the bird and its relation to the surrounding objects. Although the bird maintains a specific speed, by flying above slower traffic and maintaining a relative speed advantage, it showcases a dynamic movement in relation to its environment. Other scenarios may depict motion, but they do not consistently represent acceleration as clearly. For instance, a tether ball spinning around a pole primarily illustrates circular motion without a change in the overall speed of the ball itself. Meanwhile, the shifting direction of hurricane winds demonstrates change in wind direction but lacks a specific velocity adjustment in the context of acceleration. Lastly, while the sports car changes direction as it rounds a turn, if it maintains the same speed throughout, it would also exhibit consistent velocity without acceleration.