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# Moments Question watch

1. How do i solve moments for a square or rectangle like this:

mirror of mass 24kg is supported by two screws 80cm apart, placed at the top. One screw come off and is going to be replaced. A helper holds the mirror with force {F } 120cm below the level of the screws. I have to find F, but i dont know how to find moments when it's a square or rectangle

Attachment 699146
2. (Original post by joyoustele)
How do i solve moments for a square or rectangle like this:

mirror of mass 24kg is supported by two screws 80cm apart, placed at the top. One screw come off and is going to be replaced. A helper holds the mirror with force {F } 120cm below the level of the screws. I have to find F, but i dont know how to find moments when it's a square or rectangle

Attachment 699146
It doesn't matter what the shape is, you know the mirror is in equilibrium which means that if you take moments about any point you should get 0.

Try taking moments about the black screw and post your working/thoughts if you get stuck.
3. (Original post by Notnek)
It doesn't matter what the shape is, you know the mirror is in equilibrium which means that if you take moments about anypoint you should get 0.

Try taking moments about the black screw and post your working/thoughts if you get stuck.
I'm so glad people like you are on TSR, my working:

I got the correct Answer. TY

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