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    Literally i over complicate everything and i just can't see the easy way to do things.

    How do i stop overcomplicating things?

    an example, i just spent 2 hours today figuring this balls out which i couldn't do the last time that question was posed to me.
    much latex incoming, much time needed.....

    PHYSICS(young modulus)
    The diagram below shows 2 wires, 1 made of steel and the other of brass, firmly clamped together at their ends. The wires have the same unstretched length and the same cross-sectional area. One of the clamped ends is fixed to a horizontal support and a Mass M is suspended from the other end, so that the wires hang vertically.

    the question was show that \dfrac{E_s}{E_b}=\dfrac{F_s}{F_b  }

    the information you're given(translated by me)
    the extension of each wire will be the same
    \Delta L_s= \Delta L_b



The wires have the same unstretched length and the same cross-sectional area

A_s=A_b

     L_s=L_b

    The teachers answers were this
    E_s = \dfrac{\sigma_s}{\varepsilon}= \dfrac{F_s}{A} \times \dfrac{L}{\Delta L}

    then

    E_b = \dfrac{\sigma_b}{\varepsilon}= \dfrac{F_b}{A} \times \dfrac{L}{\Delta L}

    \therefore \dfrac{E_s}{E_b}= \dfrac{F_s}{F_b} where all the terms cancel

    however this is my working

     E_s=\dfrac{F_sL_s}{A_s \Delta L_s}

    E_s=\dfrac{F_s}{A_s {{\varepsilon}_b}}

    A_s=\dfrac{F_s}{E_s {{\varepsilon}_b}}

    A_b=\dfrac{F_b}{E_b {{\varepsilon}_s}}



\therefore \dfrac{F_s}{E_s {{\varepsilon}_b}}=\dfrac{F_b}{E  _b {{\varepsilon}_s}}



cancelling gives



\dfrac{F_s}{E_s}=\dfrac{F_b}{E_b  }



F_s E_b=F_b E_s



\dfrac{F_s}{F_b}=\dfrac {E_s}{E_b}

    how do i stop all this complicatedness?
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    (Original post by thefatone)
    Literally i over complicate everything and i just can't see the easy way to do things.

    How do i stop overcomplicating things?
    This is very generalised but take your time and don't be afraid to change perspectives
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    (Original post by LightYagamiWins)
    This is very generalised but take your time and don't be afraid to change perspectives
    Let me give an example, i see no way to do a maths question lets say, i stress myself for about 1 hour and i still can't get an answer, so i start turning to more complicated/ridiculous methods of solving an question

    just like people will turn to more extreme methods if they don't get what they want(sometimes)
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    Also, don't be afraid to go back to basics!
    Look at what the question asks for then look at the information given, and how this fits together. (may it be a basic equation or rearrangement) Basics along with a change in perspective or a fresh start always helps.

    For maths, i find it very easy to see complicated integrals and think 'ooh, obviously parts' When there is a clear substitution to put in, so i force myself instead to go back to basics and look at the integrals constituents before i make a judgement.
    Stress is of no use to you if you can't control it! Stressing is the last thing you want to do in an exam! (i know it's involuntary, but you can train yourself to be calmer)

    Extreme methods are rarely tested, i've only ever had one physics question that was absolutely extreme, about particles in the lungs on a mountain (ew)
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    (Original post by The-Spartan)
    Also, don't be afraid to go back to basics!
    Look at what the question asks for then look at the information given, and how this fits together. (may it be a basic equation or rearrangement) Basics along with a change in perspective or a fresh start always helps.

    For maths, i find it very easy to see complicated integrals and think 'ooh, obviously parts' When there is a clear substitution to put in, so i force myself instead to go back to basics and look at the integrals constituents before i make a judgement.
    Stress is of no use to you if you can't control it! Stressing is the last thing you want to do in an exam! (i know it's involuntary, but you can train yourself to be calmer)

    Extreme methods are rarely tested, i've only ever had one physics question that was absolutely extreme, about particles in the lungs on a mountain (ew)
    Basics aren't the problem here. Perspective i think is the problem. I see no way to do this question so i go to more extreme and complicated methods to complete the question. Of course there are always easier ways to do things but i can't find that way.
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    I feel you.
    I was doing a maths past paper (GCSE), and instead of doing the easy thing (1*1 = 1, 1/8 * 16 = 2), I went ahead and started working out unknown lengths using pythagoras, trigonometry etc. before finding the area of the shape
    And another time I couldn't see the two brackets for factorising the equation (36x^2 - 65x + 25 = 0) and so I went ahead and did the whole quadratic formula on it... on a non-calculator paper...
    Spoiler:
    Show
    I got them right tho
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    (Original post by surina16)
    I feel you.
    I was doing a maths past paper (GCSE), and instead of doing the easy thing (1*1 = 1, 1/8 * 16 = 2), I went ahead and started working out unknown lengths using pythagoras, trigonometry etc. before finding the area of the shape
    And another time I couldn't see the two brackets for factorising the equation (36x^2 - 65x + 25 = 0) and so I went ahead and did the whole quadratic formula on it... on a non-calculator paper...
    Spoiler:
    Show
    I got them right tho
    Same thing but with physics ..... ppl might say practise but all the questions are different in physics, i mean with maths things are narrowed down since the principle is the same and the situations they apply that principle to are minimal. The situations are generally similar but with physics they fly around the whole course and pick out random things and apply random stuff.
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    (Original post by thefatone)
    Same thing but with physics ..... ppl might say practise but all the questions are different in physics, i mean with maths things are narrowed down since the principle is the same and the situations they apply that principle to are minimal. The situations are generally similar but with physics they fly around the whole course and pick out random things and apply random stuff.
    It's still practise, just with a different focus.

    In maths, the techniques themselves are quite complicated. So you have to practise doing them.

    In physics, the technique itself is often simpler - but you have to work out which technique to use. The best way to get better at this IS practise.

    Other things that can help are knowing your specification very well so that you know what kind of things you're likely to be asked for. More generally, being very familiar with a topic eventually you get to a stage where you can intuit whether a problem is going to be tractable or not.
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    (Original post by thefatone)
    Basics aren't the problem here. Perspective i think is the problem. I see no way to do this question so i go to more extreme and complicated methods to complete the question. Of course there are always easier ways to do things but i can't find that way.
    Refuse to do anything that looks ugly. If it's not got an elegant solution, it's not worth your time - you just have to find the solution,

    For instance, with the original question, you need to reason that Force is proportional to extension. That's all you need to know, everything else is superfluous.
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    (Original post by lerjj)
    It's still practise, just with a different focus.

    In maths, the techniques themselves are quite complicated. So you have to practise doing them.

    In physics, the technique itself is often simpler - but you have to work out which technique to use. The best way to get better at this IS practise.

    Other things that can help are knowing your specification very well so that you know what kind of things you're likely to be asked for. More generally, being very familiar with a topic eventually you get to a stage where you can intuit whether a problem is going to be tractable or not.
    Ok and i do agree with you however i can't practise it when i don't understand. I literally need someone by me 24/7 for me to question them on how this works or how that works etc.

    (Original post by lerjj)
    Refuse to do anything that looks ugly. If it's not got an elegant solution, it's not worth your time - you just have to find the solution,

    For instance, with the original question, you need to reason that Force is proportional to extension. That's all you need to know, everything else is superfluous.
    I can't because that might come up in my AS mock this year in about 8 days.
    i agree but i can't just remember the solution, since the technique applied is different everytime.

    for example the first post i made which i edited and showed my working and the teachers working. I turn to more and more extreme methods when i can't find one which works.
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    (Original post by lerjj)
    Refuse to do anything that looks ugly. If it's not got an elegant solution, it's not worth your time - you just have to find the solution,

    For instance, with the original question, you need to reason that Force is proportional to extension. That's all you need to know, everything else is superfluous.
    See unfortunately this is not always true, maybe for A level, definitely not for uni.
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    (Original post by langlitz)
    See unfortunately this is not always true, maybe for A level, definitely not for uni.
    I can't ignore these questions, there about 100% chance they'll put something in i can't answer
 
 
 
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