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A body falls freely from the top of a tower.it covers 36percent of the total height in the last second,before striking the ground the height of the tower(g=10)a)50m. b)75m.c)100m. d)125m. |
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Answer» e the height of the building and t be the time to fall through this height H. Then H = ½ g t^2 = 5 t^2. -- (1) In (t-1) SECOND the distance traveled is 1 - 0.36 H = 0.64 H. 0.64 H = 5 (t-1)^2.------(2) on doing (2) / (1)we GET 0.64 = (t-1)^2/ t^2 Or 0.8 = (t-1) / t Solving we get t= 5 second. Using (1) we get H = 125 m |
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