Ok, i have a big exam in january, and I am picking through stuf i need to brush up on I found moments and I was wondering if I could get a bit of help

Right, I pretty much know how to choose the points of force upon a thing, say a plank with a person and a mass and a pivot underneither has the pressure of the pivot, froce of gravity, the person and the mass right ? what I dont know EXACTLY how to do is check to see if they are in equalibrium

Could someone possibly explain it to me ?

thanks