Question

An object is thrown upward at an angle θ above the ground, eventually returning to earth. (a) Is there any place along the trajectory where the velocity and acceleration are perpendicular? If so, where?

A) No, velocity and acceleration are never perpendicular along the trajectory.
B) Yes, at the highest point of the trajectory.
C) Yes, at the initial launch point.
D) Yes, at the midpoint of the trajectory.

Answer 1

The velocity and acceleration vectors are perpendicular at the highest point of the trajectory.

Step-by-step explanation:

The correct answer is B) Yes, at the highest point of the trajectory.

At the highest point of the trajectory, the object briefly comes to a momentary stop before it starts to fall back down. At this point, the velocity of the object is zero, and the acceleration due to gravity is downward. Since the velocity and acceleration vectors are orthogonal (perpendicular) to each other, they are perpendicular at the highest point of the trajectory.