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If a body travels half its total path in the last 1.10 s of its fall from rest, find the total time of its fall (in seconds).

User Yusijs
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1 Answer

3 votes

Answer:3.75 s

Step-by-step explanation:

Given Body travels half of its motion in last 1.1 sec

Let h be the height and t be the total time taken

here initial velocity is zero


h=ut+(gt^2)/(2)


h=0+(gt^2)/(2)


h=(gt^2)/(2)------1

Now half of the distance traveled will be in t-1.1 s and half distance traveled is in last 1.1 s


(h)/(2)=(g\left ( t-1.1\right )^2)/(2)-----2

from 1 & 2 we get


gt^2=2g\left ( t-1.1\right )^2


t^2-4.4t+2.42=0


t=(4.4\pm √(4.4^2-4\left ( 1\right )\left ( 2.42\right )))/(2)


t=(4.4\pm 3.11)/(2)

Therefore two value of t is satisfying the equation but only one value is possible

therefore t=3.75 s

User Francesco Serra
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