Q19 of 59 Page 254

A girl running a race accelerates at 2.5 ms-2 for the first 4 s of the race. How far does she travel in this time?

Acceleration = a =2.5 ms-2

Time of Acceleration = t = 4 s


Initial velocity = u = 0 ms-1


Now, from the equations of motion we know that,





s = 20 m


Hence, the girl travels 20 m in this time.


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