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# M3 Edexcel Statics of Rigid Bodies, Force acted on an object (sliding/toppling) watch

1. https://gyazo.com/cd8ecfbc5966239cda66f850e440e422
https://gyazo.com/1c1c1a70f77139d0c4ff04b70f75a0a1
Above are the questions and the solutions from its solution bank.
In the solutions, when working out Qa, the direction of friction is taken as downwards, and the question is solved by taking moment about point A. However what I don't understand is why when working out Qb, the direction of friction is taken as parallel to the plane, instead of going downwards to the plane like in Qa? Thanks in advance.
2. Huh? i don't see the part where they say friction acts downwards
However what I don't understand is why when working out Qb, the direction of friction is taken as parallel to the plane, instead of going downwards to the plane like in Qa? Thanks in advance.
Although the image at the top of your second attachment appears to show a force "F" acting downwards, in fact the F refers to the arrow going left from A The downward arrow relates to the Mg.

Rather a poor diagram.
4. (Original post by ghostwalker)
Although the image at the top of your second attachment appears to show a force "F" acting downwards, in fact the F refers to the arrow going left from A The downward arrow relates to the Mg.

Rather a poor diagram.
Oh it's you again . I love you man, thanks.
Oh it's you again . I love you man, thanks.

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