Answer
The correct answer is:
(c) 2.1 m/s
Work Step by Step
The correct answer is:
(c) 2.1 m/s
The area under the velocity versus time graph is the displacement.
Each block in the graph is $1~m/s \times 120~s = 120~m$
During the entire 30.0 min, there are 26 blocks above the x-axis and 6 blocks below the x-axis. The blocks below the x-axis indicate a negative displacement.
The 26 blocks above the x-axis indicate a displacement of $(26)(120~m) = 3120~m$, which is a distance of $3120~m$
The 6 blocks below the x-axis indicate a displacement of $-(6)(120~m) = -720~m$, which is a distance of $720~m$
The total distance is $3120~m+720~m = 3840~m$
The average speed is: $\frac{distance}{time}$
The average speed is: $\frac{3840~m}{1800~s} = 2.1~m/s$
