OR: Is it possible for an object’s velocity to be in the direction opposite to its acceleration?
OR : Velocity and acceleration do not need to be directed towards the same way.
Yes, it is possible when the object has negative acceleration or retardation. When a body is undergoing retardation, the body is going in one direction but is being acted upon by a force in opposite direction. So, the acceleration will also be in the opposite direction. Thus, if the object is going towards east (has an eastward velocity) but is acted by an opposite force (in westward direction), the acceleration will be towards the west.
For example, on the application of brakes on a moving vehicle, the direction of its deceleration is opposite to that of its motion.
Similarly, in simple harmonic motion, when a body is moving towards east from its mean position, the direction of its velocity will be eastward. But, since the acceleration is always directed towards the mean position, the direction of its acceleration will be towards west.
[Read: Motion in a Straight Line]
A player hits a baseball at some angle. The ball goes high up in space. The player runs and catches the ball before it hits the ground. Which of the two (the player or the ball) has greater displacement?