Final answer:
The acceleration of an object changing its velocity is in the direction of the change in velocity. It aligns with v2 if the object is increasing its speed, or it's opposite to v2 if the object is slowing down.
Step-by-step explanation:
When an object changes its velocity from v1 to v2 over a time interval Δt, the direction of the object's acceleration depends on how the change in velocity occurs. If the object is speeding up in the direction it is moving, acceleration would be in the same direction as v2. Conversely, if the object is slowing down, the acceleration would be in the direction opposite to its current velocity vector.
The correct answer is that the acceleration is in the direction of the change in velocity. This can be in the direction of v2 if the object speeds up, or in the opposite direction if it slows down. Therefore, if v2 is greater than v1 and in the same direction, answer b) In the direction of v2 is correct. If v2 is less than v1 and in the same direction, then the correct answer would be d) In the opposite direction to v2.