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Drops of water fall at regular intervals from the roof of a building of height H = 16m, the first drop striking the ground at the same moment as the fifth drop detaches from the roaf. Find the distance between the successive drops. |
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Answer» Solution :Step -I : Time taken by the first drop to touch the ground `=t=sqrt((2h)/g) ` For h=16m, `t=sqrt((2 XX 16)/g) =4sqrt(2/g)` Time interval between two drops is `t_("interval")=((1)/(n-1))t=(1/4)t=sqrt(2/g)` where n=number of drops. Step -ii : DISTANCE between first and SECOND drops `=S_(1)-S_(2)=1/2 gt_("interval")^(2) [4^(2)-3^(2)]=7M` Distance between second and third drops `=S_(2)-S_(3)=1/2 "gt"_("internal")^(2) [3^(2)-2^(2)]=5m` Distance between third and fourth drops `=S_(3)-S_(4)=1/2 "gt"_("internal")^(2) [2^(2)-1^(2)]=3m` Distance between fourth and fifth drops `=S_(4)-S_(5)=1/2 "gt"_("interval")^(2) [1^(2)-0]=1m`. |
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