I do not understand how to solve static equilibrium questions. Like those: Or this one http://www.chegg.com/homework-help/...sitionby-a-pin-and-cable-as-shown-in--q701621 The second one with the pin is especially hard, imo. I don't even know what the basic equation here is. The book dosen't tell you this. It's always [itex]\Sigma[/itex][itex]\tau[/itex]=....... something else. So I do have to create my own equation each time, basically. Is this correct? Depending on whatever the problem is. I don't get it. Can someone please explain this to me?