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Grade Select GradeMechanics

two balls are dropped from the top of a cliff at a time interval of 2 seconds the first ball hits the ground rebounds elasticalyy (esssentialy reversing direction instantly without
losin speed) and collides with the second ball at height of55 m above the ground how high is the top of the cliff

Profile image of Yashishvin Pothuri
11 Years agoGrade Select Grade
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Profile image of Yashishvin Pothuri
11 Years ago
finally after a long workout did manage to solve the problem
here is the solution
consider the height of the tower to be h
so the first ball will take t seconds to cover the distance of(h-55) m  and the second ball will take t+ 2 seconds to cover the same distance in that 2 seconds the first ball will cover 110m
so in the case of the first ball we have two types of motions upward and downward it will cover both the types of motions in equal time intervals so we get the initial velocity which is the final velocity for the distance of (h-55) with which we get the distance of h-55 finally we get the awnser as180m
this is onemethod ialso manged tofigure out another one but it is slightly complicated