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M2 Centre of Mass (Simple understanding query) Watch

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    Can someone confirm how I can take moments here without masses?

    I used a c.o.m equation, divided by total lengths and got the answer in the marks scheme but they divide by 3 in there and I'm not sure why the 3 works - is it because there are 3 masses of equal weight so the weights all cancel out?​
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    (Original post by Ki Yung Na)



    Can someone confirm how I can take moments here without masses?

    I used a c.o.m equation, divided by total lengths and got the answer in the marks scheme but they divide by 3 in there and I'm not sure why the 3 works - is it because there are 3 masses of equal weight so the weights all cancel out?​
    You assume a certain mass per unit length.
    Each part of the framne can be repalced by a mass placed at its mid-point hence 3 masses.
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    (Original post by Ki Yung Na)



    Can someone confirm how I can take moments here without masses?

    I used a c.o.m equation, divided by total lengths and got the answer in the marks scheme but they divide by 3 in there and I'm not sure why the 3 works - is it because there are 3 masses of equal weight so the weights all cancel out?​
    The centre of mass equation is when you taking moments about a given point in the X and Y direction.
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    (Original post by brianeverit)
    You assume a certain mass per unit length.
    Each part of the framne can be repalced by a mass placed at its mid-point hence 3 masses.
    That's a good explanation for my fluffy description. Thanks for the clarification!

    (Original post by Jai Sandhu)
    The centre of mass equation is when you taking moments about a given point in the X and Y direction.
    That isn't quite what I was asking about.
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    (Original post by Ki Yung Na)
    That isn't quite what I was asking about.
    Was just saying as you were referring to it as the centre of mass equation which is isnt really.
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    (Original post by Jai Sandhu)
    Was just saying as you were referring to it as the centre of mass equation which is isnt really.
    "A com equation" not "the equation" - in other words; I didn't say that it wasn't taking moments but rather I was asking how it was.
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    There's been a misconception during reading and your point might have confused someone else that's why i'm picking up on it.
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    (Original post by Ki Yung Na)
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    There's been a misconception during reading and your point might have confused someone else that's why i'm picking up on it.
    Probably, sorry for the confusion.
 
 
 
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