What is the number of poles initially ?

rengaraj
@rengaraj-89Rrct โ€ข Oct 25, 2024

Sir / madam,
My question is

A 1 KM long wire is held by 'n' poles. If one pole is removed the length of the gap increases by 5/3 meters. What is the number of poles initially ?

Advance Thanks,
R.Rengaraj
{NIT 23/2007/Pg 3 (Infosys Part-1)}
{On this forum my 12th Question.

Replies

Welcome, guest

Join CrazyEngineers to reply, ask questions, and participate in conversations.

CrazyEngineers powered by Jatra Community Platform

  • yadavundertaker mohit

    @yadavundertaker-0p3HBs Nov 25, 2009

    length of gap with n poles = 1000/(n-1)

    new length of gap = 1000/(n-2)

    according to question

    1000/(n-2)= 5/3 + 1000/(n-1)

    1000(n-1-n+2)/(n-1)(n-2)=5/3


    on solving n = 26

    number of poles initially is 26.....
    1000/(n-1)(n-2)= 5/3

  • rengaraj

    @rengaraj-89Rrct Nov 25, 2009

    Sir,
    I got the question from an book but, the solution was 25. But i can't get the steps worked.
    But i will try once more.
    R.Rengaraj

  • yadavundertaker mohit

    @yadavundertaker-0p3HBs Nov 25, 2009

    the no. of poles will be 25 after one pole is removed..

    steps

    length of gaps = total length in meter /(no. of ploes -1) [we minus 1 because a gap will be exist b/w two poles]

  • CIVILPRINCESS

    @civilprincess-308hDv Nov 26, 2009

    yes the number of poles initially is 26.by simplifying the equation yadav got we get
    n^2-3n-598=0
    26 solves it.

  • yadavundertaker mohit

    @yadavundertaker-0p3HBs Nov 28, 2009

    hi rengraj

    did you check the answer again?....

  • rengaraj

    @rengaraj-89Rrct Nov 29, 2009

    Sir,
    The solution is 25.
    Thanks,
    R.Rengaraj

  • Anil Jain

    @CrazyBoy Nov 29, 2009

    if n poles (n-1) gaps of each 1000/(n-1) width
    if n-1 poles (n-2) gaps of each 1000/(n-2) width
    so,
    1000/(n-2) -1000/(n-1)=5/3
    1000(1/(n-2) -1/(n-1))=5/3

    so number of poles initially would be 26 only.

  • rengaraj

    @rengaraj-89Rrct Nov 30, 2009

    Sir,
    This is an Infosys question. The given answer is 25.
    R.Rengaraj