Consider the following velocity and time graph: Which one of the follo

Consider the following velocity and time graph:
Which one of the following is the value of average acceleration from 8 s to 12 s?

8 m/s²
12 m/s²
2 m/s²
-1 m/s²
This question was previously asked in
UPSC NDA-2 – 2018
The correct value of average acceleration from 8 s to 12 s is -1 m/s².
– Average acceleration is defined as the change in velocity divided by the time interval.
– From the given velocity-time graph, the velocity at t = 8 s is approximately 10 m/s.
– From the graph, the velocity at t = 12 s is approximately 6 m/s.
– The time interval is Δt = 12 s – 8 s = 4 s.
– The change in velocity is Δv = v(12s) – v(8s) = 6 m/s – 10 m/s = -4 m/s.
– Average acceleration = Δv / Δt = (-4 m/s) / (4 s) = -1 m/s².
– A negative acceleration indicates that the velocity is decreasing.
– In a velocity-time graph, the slope of the line represents instantaneous acceleration. For average acceleration over an interval, we consider the endpoints of the interval.