Q34 of 35 Page 55

A body travels half of its total path in the last second of its free fall from rest. The duration of the fall is nearly?

Since this is a free fall:

u = 0 and a = g = 9.8 ms–2


Let the total time of free fall be T, and total distance travelled be H.


We use the second equation of motion:


..1


Given:


A body travels half of its total path in last second. This also means that the body travels half of its total path in (T – 1) s.


Now, using 1:




..2


Also,


..3


Equating 2 and 3, we get:





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