A baseball is thrown from the outfield toward the catcher. When the ball reaches its highest point, which statement is true? A. Its velocity and its acceleration are both zero. B. Its velocity is not zero, but its acceleration is zero. C. Its velocity is perpendicular to its acceleration. D. Its acceleration depends on the angle at which the ball was thrown. E. None of statements (A) through (D) is true.
Hint: The pace at which the position changes is called velocity. The displacement or position shift (a vector quantity) per time ratio is the average velocity. A determination of an object's speed and direction of motion is referred to as velocity.
Complete answer: Due to the fact that velocity is a vector, it may vary in magnitude or direction. As a result, acceleration is described as a change of speed or direction or both. Keep in mind that while acceleration still occurs in the direction of velocity change, it does not always occur in the direction of motion.
A. In this case, both velocity and acceleration cannot be equal to zero. Hence this is not the correct answer. B. The acceleration is not equal to zero, but it is directed downwards. Hence this is not the correct answer. C. The ball's vertical velocity is temporarily zero at the highest point on the path. As a consequence, the ball's resultant velocity is horizontal at this point, and its acceleration is still downward. Thus, the velocity is perpendicular to the acceleration. Hence this is the correct answer. D. The acceleration of the baseball does not depend on the angle at which it is thrown. Hence this is not the correct answer. E. Since option (C) is the correct answer, this option is not correct.
Therefore, the correct option is C.
Note: The velocity's sign is determined by the coordinate system used to describe the position. A positive velocity indicates that the object is moving in the positive direction as defined by the coordinate system, while a negative velocity indicates that the object is moving in the opposite direction.