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    Hey so im going to add an attachment with this. I've spent ages trying to figure this out and im still struggling. Our teachers this year for physics have been continuously changing and i really don't understand much of it. Definitely not P3. PLEASE could anyone help me with any of the following questions. I would be soooooo grateful.
    I'm being honest when i say ive been trying for long. My teacher will freak if i don't complete this work and im a good A/A* student so can anyone please help me with this. It will help me to do the rest which are a little similar.
    I really need some help and even went through the effort of making the diagram.

    I will give reps to any helpful replies.
    Thanks in advance.

    hwk.docx
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    (A2 PHY student here)

    Despite the diagram (which is confusing):

    A)i) W = mg = 2*9.81 etc

    ii) Moment = force * distance

    force = weight


    C)Ok the Moments are equal on both sides so 2 * 9.81 * 0.08 = m * 9.81 * 0.8

    cancel G's

    0.16 = 0.8m

    Therefore mass of B = 0.2kg

    D) (got dinner now gtg sorry )

    Someone can help you with D before I get back!
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    DL: if the 1m ruler is massive you'll have to consider the effect of a weight force acting at it's centre of mass in addition to the setup in the diagram. I think you'll have to assume the new ruler is uniform.

    Q. seems just to be asking which direction mass B needs to be moved in to maintain balance.
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    (Original post by Dancatpro)
    (A2 PHY student here)

    Despite the diagram (which is confusing):

    A)i) W = mg = 2*9.81 etc

    ii) Moment = force * distance

    force = weight


    C)Ok the Moments are equal on both sides so 2 * 9.81 * 0.08 = m * 9.81 * 0.8

    cancel G's

    0.16 = 0.8m

    Therefore mass of B = 0.2kg

    D) (got dinner now gtg sorry )

    Someone can help you with D before I get back!
    Oh thank you. Sorry before the diagram i missed a bit. It was meant to say... A teacher balance.s a metre rule on a wooden block using two masses.
    Don't know if that will help you understand it better but thanks so much
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    (Original post by Aty100)
    Oh thank you. Sorry before the diagram i missed a bit. It was meant to say... A teacher balance.s a metre rule on a wooden block using two masses.
    Don't know if that will help you understand it better but thanks so much
    No Problem!
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    (Original post by Dancatpro)
    No Problem!
    for question D, does the mass B just need to be bought closer to the pivot?
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    (Original post by Aty100)
    for question D, does the mass B just need to be bought closer to the pivot?
    Yep, weight of rod acts to the right of the pivot

    Think about it like this.

    Moment going anticlockwise = moment clockwise

    moment of A = moment of B + moment of rod

    moment of A stays the same

    can work out moment of rod

    then subtract moment of rod from moment of A = moment of B

    moment of B divided by mass = distance from pivot.


    When doing a moments question, you should get full marks every time if you write out an equation like that (above) and use correct notation.


    Private message me if you need any further help, although rather busy with uni applications and mocks
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    (Original post by Dancatpro)
    Yep, weight of rod acts to the right of the pivot

    Think about it like this.

    Moment going anticlockwise = moment clockwise

    moment of A = moment of B + moment of rod

    moment of A stays the same

    can work out moment of rod

    then subtract moment of rod from moment of A = moment of B

    moment of B divided by mass = distance from pivot.


    When doing a moments question, you should get full marks every time if you write out an equation like that (above) and use correct notation.


    Private message me if you need any further help, although rather busy with uni applications and mocks
    Aww thanks so much, i cant thank you enough . I also just finished my mocks and need to write a personal statement to apply to sixth forms. Good luck with the applications and mocks. You will do amazing. If you don't mind and have some time some day i would love it if you could help me out with my personal statement . I want to go to this really good new sixth form and all the people that apply are A and A* student so there is a lot of competition i really need a amazing personal statement. It would be amazing if you could help but of course i understand if you dont have much time seeing as your very busy yourself and need to do your own applications first, but if you ever do have some time please PM me. Im thinking of doing Maths Biology Chemistry and economics. Once again thanks soo much for your help xxx
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    (Original post by Aty100)
    Aww thanks so much, i cant thank you enough . I also just finished my mocks and need to write a personal statement to apply to sixth forms. Good luck with the applications and mocks. You will do amazing. If you don't mind and have some time some day i would love it if you could help me out with my personal statement . I want to go to this really good new sixth form and all the people that apply are A and A* student so there is a lot of competition i really need a amazing personal statement. It would be amazing if you could help but of course i understand if you dont have much time seeing as your very busy yourself and need to do your own applications first, but if you ever do have some time please PM me. Im thinking of doing Maths Biology Chemistry and economics. Once again thanks soo much for your help xxx
    Thanks! Already got an unconditional from Sussex and offers from all the other uni's I applied too (A:A:A:C in my mocks , maths,physics,computing,chemistr y respectively)

    Not really that busy, still have time to play games for 1-3 hours a day LOL !

    Would be happy to help you with your personal statement, I have my big computing project due Wednesday so I could help you out after that!
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    (Original post by Dancatpro)
    Thanks! Already got an unconditional from Sussex and offers from all the other uni's I applied too (A:A:A:C in my mocks , maths,physics,computing,chemistr y respectively)

    Not really that busy, still have time to play games for 1-3 hours a day LOL !

    Would be happy to help you with your personal statement, I have my big computing project due Wednesday so I could help you out after that!

    OMG you are amazing !!!! Yes of course finish you project first, Good luck with it. The application deadline for my sixth form is first week of feb so we have enough time. I literally cannot explain how delighted i am right now. Thank you so much. xxx You are awesome.
    making CVs and personal statements is kind of a weak point for me .

    Seriously thank you so much. You're soo kind. I never thought someone would actually help me. We need more kind hearted people like you xx
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    (Original post by Aty100)
    OMG you are amazing !!!! Yes of course finish you project first, Good luck with it. The application deadline for my sixth form is first week of feb so we have enough time. I literally cannot explain how delighted i am right now. Thank you so much. xxx You are awesome.
    making CVs and personal statements is kind of a weak point for me .

    Seriously thank you so much. You're soo kind. I never thought someone would actually help me. We need more kind hearted people like you xx
    Funny thing is, I joined The Student Room earlier today !

    Anyway, send me a copy at any time (even before Wednesday) and I will have enough time to suggest some changes (seriously though anytime from now until when it's due is fine!).

    Writing stuff like this was my weak point too until I applied through UCAS.

    Will talk soon!
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    (Original post by Dancatpro)
    Funny thing is, I joined The Student Room earlier today !

    Anyway, send me a copy at any time (even before Wednesday) and I will have enough time to suggest some changes (seriously though anytime from now until when it's due is fine!).

    Writing stuff like this was my weak point too until I applied through UCAS.

    Will talk soon!

    Well thank God you joined today. Dunno what i would have done without you haha
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    (Original post by Aty100)
    Well thank God you joined today. Dunno what i would have done without you haha
    Joinedup would have helped you!
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    (Original post by Dancatpro)
    Joinedup would have helped you!
    True
 
 
 
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