Final answer:
The acceleration of the object, calculated by using the change in velocity divided by the time taken and then converting the result to the desired units, is 8 km/hr².
Step-by-step explanation:
To calculate the acceleration of the object, we can use the formula for acceleration (a), which is the change in velocity (Δv) divided by the change in time (Δt):
a = Δv / Δt
First, we need to convert the final velocity from km/hr to m/s to match the time given in seconds:
24 km/hr = (24 × 1000 m) / (3600 s) = 6.67 m/s
Now, we'll find the change in velocity:
Δv = final velocity - initial velocity = 6.67 m/s - 0 m/s = 6.67 m/s
Given that the time is 3 seconds, the calculation for acceleration is:
a = 6.67 m/s / 3 s = 2.22 m/s²
However, the answer choices are in km/hr². To convert 2.22 m/s² back to km/hr²:
(2.22 m/s²) × (3600 s/hr) × (1 hr/1000 m) = 8 km/hr²
Therefore, the correct answer is A) 8 km/hr².