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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Ki Yung Na
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- 11-05-2015 11:35
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brianeverit
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- 11-05-2015 12:19
(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?
Each part of the framne can be repalced by a mass placed at its mid-point hence 3 masses. -
Jai Sandhu
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- 11-05-2015 12:36
(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? -
Ki Yung Na
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- 11-05-2015 13:55
(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.
(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.Last edited by Ki Yung Na; 11-05-2015 at 13:58. -
Jai Sandhu
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- 11-05-2015 14:09
(Original post by Ki Yung Na)
That isn't quite what I was asking about. -
Ki Yung Na
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- 11-05-2015 14:15
(Original post by Jai Sandhu)
Was just saying as you were referring to it as the centre of mass equation which is isnt really.
Spoiler:ShowThere'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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- 11-05-2015 14:33
(Original post by Ki Yung Na)
Spoiler:ShowThere'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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