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Question
Figure given below shows a velocity-time graph for a car starting from rest. The graph has three parts AB, BC and CD.
(a) Is the magnitude of acceleration higher or lower than that of retardation ? Give a reason .
(b) Compare the magnitude of acceleration and retardation .
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Solution
(a) The magnitude of acceleration is lower as the slope of line AB is less than that of line CD.
(b) Slope of line AB = vo/t
Slope of line CD = vo/0.5t
Slope of line AB/Slope of line CD = (vo /t)/(vo /0.5t)
Slope of line AB:Slope of line CD :: 1:2.
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