IMAT 2013 Q54 physics

HEY, I always get confused in which direction should I count the weight of the beam for , like the part that says ‘‘the weight of the beam also accounts for the clockwise moment’’
I know there was a lot of question like this but how can i make sure in which direction the weight of the beam or anything else instead of this beam should be considered toward? this question was clockwise ,then how did we conclude that?

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Remember the weight acts downwards on the CENTER of the beam. And the anticlockwise/clockwise direction depends on where the pivot is placed. Here are some diagrams. Unless there is negligible weight of the beam or the pivot is right at the center it is always counted for. Hope this helps!

Imgur

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THANK YOU for the clarification ,that was really helpful!

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how do we solve this quetion?

like in the diagram, you can use moments → anticlockwise moment = clockwise moment.

Super awesome and accurate explanation- I’ve been getting this question loads in regards to the past paper solution so I am so glad to see my solution makes a little sense!!

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