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# M1 Moments Questions watch

1. Hiya there,

I'm doing a Mechanics M1 question but I can't seem to get my head around it and would like some help or method on how to go around it since i've been stuck on it for some time now.

The question is:
A uniform bar AB of length 2.8 m and weight 80 N has loads of 20 N and 40 N attached at A and B respectively. If the bar balances in a horizontal position when smoothly supported at C, find the distance of C from A.

This is my current diagram (If its correct?)
Thanks
Attached Images

2. (Original post by Choco-Omar)
Hiya there,

I'm doing a Mechanics M1 question but I can't seem to get my head around it and would like some help or method on how to go around it since i've been stuck on it for some time now.

The question is:
A uniform bar AB of length 2.8 m and weight 80 N has loads of 20 N and 40 N attached at A and B respectively. If the bar balances in a horizontal position when smoothly supported at C, find the distance of C from A.

This is my current diagram (If its correct?)
Thanks
You do not have the support C in your diagram
3. (Original post by TenOfThem)
You do not have the support C in your diagram
Yeah, I think it should be like this:
Attached Images

4. (Original post by Choco-Omar)
Yeah, I think it should be like this:
Yes
You need to label the distance AC as x or something .... Then take some moments
5. (Original post by TenOfThem)
Yes
You need to label the distance AC as x or something .... Then take some moments
Right.. So if the distance from AC is x, then the distance from C to the centre is (1.4-x) .

The moments calculations would be around C correct?
So it would be..
20(x) + 80(1.4-x) + 40(2.8-x) ?

Sorry, Im kind of getting confused with which calculations to be taken.
6. (Original post by Choco-Omar)
Right.. So if the distance from AC is x, then the distance from C to the centre is (1.4-x) .

The moments calculations would be around C correct?
So it would be..
20(x) + 80(1.4-x) + 40(2.8-x) ?

Sorry, Im kind of getting confused with which calculations to be taken.
Yes for lengths
You need to consider direction for your moments and you need an equation

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