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A stone falls freely from rest and the total distance covered by it in the last second of its motion equals the distance covered by it in the first three seconds of its motion. The stone remains in the air for |
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Answer» dsThe Formula used to calculate the distance covered in nth second:SN = ut + 1/2a(2n -1)Calculating the first distance(s1) USING the formula mentioned above:= g/2(2 x 1 - 1)= 10/2(2 x 1 - 1)= 5 (1)= 5 metersCalculating the second distance (s2) using the formula mentioned above:= g / 2 (2 x 2 - 1)= 10/2(4 - 1)= 5 (3)= 15 metersCalculating the third distance (s3) using the formula mentioned above:= g / 2 (2 x 3 - 1)= 10/2 (6 - 1)= 5 (5)= 25 metersAdding all the DISTANCES which we obtained we get:= 5 + 15 + 25= 45 metersNow calculating time taken:g / 2(2T - 1) = 45Substituting all the known values into this equation we get:5(2T - 1) = 4510T - 5 = 4510T = 50T = 50 / 10T = 5 secondsTherefore, the time the stone remains in the air is for 5 seconds. |
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