Question
Tue March 13, 2012 By:
 

a ball is dropeed from a height of 48m and rebounds two thirds of the distance it falls.if it continues to fall and rebound in this way how far will it travel before coming to rest

Expert Reply
Fri March 16, 2012
Height from which it falls=48 so 1ST Time distance travelled=48 then it rebounds and so covers 2/3*48 and comes down to travel 2/3*144 again so 2nd Time distance travelled=2*(2/3)*48 and so on, Total D=48+2*(2/3)*48+2*(2/3)(2/3)48+....... Apply sum to infinite GP D=48[1+2*2/3+2*(2/3)2+......] =48[1+2{2/3+(2/3)2+(2/3)3+.....infinity}] =48[1+2(2)] =240m
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