Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    1
    ReputationRep:
    A screw jack has a single start thread of pitch 6 mm and an
    operating handle of radius 450 mm. The following readings of
    load and effort were taken during a test on the jack.
    Load (kN) 0 1 2 3 4 5 6 7 8 9 10
    Effort (N) 2.2 6.6 11.8 17.0 22.2 27.2 32.2 36.8 41.4 46.9 52.4
    (a) Plot a graph of effort against load and from it, determine the
    law of the machine.
    (b) Plot a graph of mechanical advantage against load.
    (c) Plot a graph of efficiency against load and state whether the
    machine is likely to overhaul.
    (d) Calculate the theoretical limiting values of mechanical
    advantage and efficiency, and state whether your graphs
    tend towards these values.
    (e) Calculate the work input and the work done against friction
    when raising the 10 kN load through a height of 50 mm.

    I am confused with the work done against friction, Is it same as work done in overcoming friction?
    Offline

    3
    ReputationRep:
    (Original post by TAREQ003)
    A screw jack has a single start thread of pitch 6 mm and an
    operating handle of radius 450 mm. The following readings of
    load and effort were taken during a test on the jack.
    Load (kN) 0 1 2 3 4 5 6 7 8 9 10
    Effort (N) 2.2 6.6 11.8 17.0 22.2 27.2 32.2 36.8 41.4 46.9 52.4
    (a) Plot a graph of effort against load and from it, determine the
    law of the machine.
    (b) Plot a graph of mechanical advantage against load.
    (c) Plot a graph of efficiency against load and state whether the
    machine is likely to overhaul.
    (d) Calculate the theoretical limiting values of mechanical
    advantage and efficiency, and state whether your graphs
    tend towards these values.
    (e) Calculate the work input and the work done against friction
    when raising the 10 kN load through a height of 50 mm.
    I am confused with the work done against friction, Is it same as work done in overcoming friction?
    Work done against = work done to overcome, you are correct.
    • Thread Starter
    Offline

    1
    ReputationRep:
    (Original post by HapaxOromenon3)
    Work done against = work done to overcome, you are correct.
    Thanks i done it
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Has a teacher ever helped you cheat?
    Useful resources

    Make your revision easier

    Maths

    Maths Forum posting guidelines

    Not sure where to post? Read the updated guidelines here

    Equations

    How to use LaTex

    Writing equations the easy way

    Student revising

    Study habits of A* students

    Top tips from students who have already aced their exams

    Study Planner

    Create your own Study Planner

    Never miss a deadline again

    Polling station sign

    Thinking about a maths degree?

    Chat with other maths applicants

    Can you help? Study help unanswered threads

    Groups associated with this forum:

    View associated groups
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Write a reply...
    Reply
    Hide
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.