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Question
A girl walks along a straight path to drop a letter in the letterbox and comes back to her initial position. Her displacement–time graph is shown in Fig.8.4. Plot a velocity-time graph for the same.
Solution
From displacement – time graph,
velocity = `"displacement"/"time"`
= `(100"m")/(50"s")`
= 2ms−1
The symmetry of the graph shows that the girl comes back to her initial position with the same velocity (2 ms−1) but in opposite direction. So, the velocity-time graph will look like
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