Q5 of 59 Page 255

The displacement of a body is proportional to the cube of the time lapsed. The magnitude of the acceleration is:

We know that,


Displacement …….1


Now, Velocity = …….2


From equations 1 and 2, we get,


Velocity …….3


Now, we also know that,


Acceleration = …….4


From equations 3 and 4, we get,


Acceleration time


Since, acceleration is directly proportional with time, so it increases with time.


Hence option A is correct.

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