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# Maths mechanic M1 moments watch

1. Could some help me with this question please

A non-uniform rod AB of length 3M and mass 5kg is suspended in equilibrium in a horizontal position by ropes attached to point P and Q of the rod. AP=1m and AQ=2.5m. The tension in both ropes are equal. Find the distance of the Center of the mass of the rod from A

I don't understand how to find the centre all I know is that the equations formed will be equal to zero
2. (Original post by Mf1999)
Could some help me with this question please

A non-uniform rod AB of length 3M and mass 5kg is suspended in equilibrium in a horizontal position by ropes attached to point P and Q of the rod. AP=1m and AQ=2.5m. The tension in both ropes are equal. Find the distance of the Center of the mass of the rod from A

I don't understand how to find the centre all I know is that the equations formed will be equal to zero
Essentially you want to be solving moments about A which gives:

where is the distance from A to the centre of mass.

You have two unknowns, but if you now take moments about P you should be able to express in terms of .
3. Here is a fully worked solution.
best,
Yahia Ezzat
Attached Files
4. math answer.docx (18.9 KB, 52 views)
5. (Original post by Yahia Ezzat)
Here is a fully worked solution.
best,
Yahia Ezzat
u

Thank u so much
6. (Original post by RDKGames)
Essentially you want to be solving moments about A which gives:

where is the distance from A to the centre of mass.

You have two unknowns, but if you now take moments about P you should be able to express in terms of .
I still don't get it I looked at the solution but I don't get how they got it could you possibly tell me what do to step by step??
7. (Original post by Mf1999)
I still don't get it I looked at the solution but I don't get how they got it could you possibly tell me what do to step by step??
Which part is it that you do not understand?
8. (Original post by Yahia Ezzat)
Here is a fully worked solution.
best,
Yahia Ezzat
9. (Original post by Yahia Ezzat)
Here is a fully worked solution.
best,
Yahia Ezzat
Please don't post full solutions - by the way I would not give you full marks for this.

You have not defined your variables or explained why you are taking moments.
10. I figured it out never mind thank you

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