A body covers 3, 6, 12, 24, ... metres in successive equal time intervals. If the total distance covered is 189 m, find the number of intervals.
Physics · Mathematical tools and vector · Sequence & Series
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Question

A body covers 3, 6, 12, 24, ... metres in successive equal time intervals. If the total distance covered is 189 m, find the number of intervals.

G1 Physics · Accepted Answer

Finite GP: Sₙ=3(2ⁿ−1)=189. Thus 2ⁿ−1=63, 2ⁿ=64 and n=6.