Final answer:
The acceleration of the object is calculated using the formula a = Δv/Δt. With a change in velocity of -4 m/s over 2 seconds, the acceleration is -2 m/s², indicating the object is decelerating.
Step-by-step explanation:
To calculate the acceleration of the object, we can use the definition of acceleration, which is the change in velocity (Δv) over the time interval (Δt) it occurs. The formula for acceleration is a = Δv/Δt, where Δv is the final velocity minus the initial velocity, and Δt is the elapsed time.
In this case, the initial velocity (v_i) is 8 m/s, the final velocity (v_f) is 4 m/s, and the time interval (Δt) is 2 seconds. The change in velocity (Δv) is then 4 m/s - 8 m/s = -4 m/s. Plugging these values into the acceleration formula gives us: a = Δv/Δt = (-4 m/s) / 2 s = -2 m/s².
Therefore, the correct answer to the question is A. -2 m/s², which indicates the object is decelerating since the acceleration is negative.