A small block slides, without friction, down an inclined plane starting from rest. Let S n be the distance travelled from time t=(n-1) to t=n. If S n S n + 1 is found to be 5/7, then value of n is?

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A small block slides, without friction, down an inclined plane starting from rest. Let       S    n   be the distance travelled from time t=(n-1) to t=n. If             S      n              S              n        +        1             is found to be 5/7, then value of n is?

Elliot Watson · Accepted Answer

Distance travelled in t sec   =      S    t    ∴      S    t    =  u  +  a  t  −  a      /    2as u=0            S      n              S              n        +        1              =            a      n      −      a              /            2              a      (      n      +      1      )      −      a              /            2        =            a      (      2      n      −      1      )      ×      2              2      a      (      2      n      +      1      )          =            2      n      −      1              2      n      +      1        =      5    7      ⇒  14  −  7  =  10  n  +  5    ⇒  4  n  =  12    ⇒  n  =  3

A small block slides, without friction, down an inclined plane starting from rest. Let S...

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