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Homework Statement
A plank of wood is attached onto the wall by a hinge. The blank is inclined at an angle of 30 degrees to the horizontal and is held stationary by a rope which is attached at the opposite end onto the wall. Label the three forces acting on the plank
Homework Equations
None
The Attempt at a Solution
I have attached a diagram I have drawn of the problem and my attempt. The tension and weight force are easy but the I am unsure about the third force exerted by the hinge/wall. The answer in the back of the book says that the third force is "the reaction force from the hinge/wall passing through the point where the weight arrow meets the tension arrow". I have no idea what or where this point is they are on about. I approached it by arguing that the hinge must exert equal and opposite forces to the weight and tension. I have drawn a vector diagram on the attachment to and labelled the third force. Is this correct and can someone please explain what this point is they are on about  there is no point where they cross?
Thanks!
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