Force on door from two hinges - easy - help anyone?

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The discussion revolves around calculating the forces on a door supported by two hinges, focusing on the torque and force balance. The door dimensions and mass are provided, with a specific emphasis on understanding the horizontal force component at the hinges. Participants suggest using a free body diagram to visualize the forces and moments acting on the door, highlighting that the vertical force at each hinge equals half the door's weight. To find the horizontal force components, it's recommended to take moments about one hinge and apply equilibrium equations. Overall, the conversation seeks clarification on the methodology for solving the torque and force problem related to the door's hinges.
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torque/force problem - two door hinges - help anyone?

A large door of height - 2.1 m - along y-axis that extends vertically upward and width - 0.95 m - along x-axis that extends outward from the hinged edge of the door. A hinge at 0.30 m from the top and a hinge at 0.30 m from the bottom, each support half the door's mass which is 28 kg.

(a) In unit-vector notation, what is the force on the door at the top hinge?
___ N i +____ N j
(b) In unit-vector notation, what is the force on the door at the bottom hinge? ___ N i +____ N j


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I don't understand where the horizontal force - vector in i direction - is coming from if there's no horizontal movement and only gravity is acting along the y-axis or j hat

so my answers for the j hat vectors are simply 9.8x14= 137.2N which is the correct answer... but i don't understand parts A and C?

help anyone?
 
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help please~!

anyone out there? i don't need to give me the answer... could anyone just point me in the right direction? how to find the i-hat vector forces in this problem?

thanksss a lot
 
Take the moment about the bottom hinge to find the answer for a) and then swap to the top hinge to find b)
 
i, too, am stuck on this problem, and what do you mean by take the moment? I am a bit rusty, and trying to remember that, but can't seem to remember... any help?
 
First you draw the free body diagram. Putting in all the forces into the diagram, there are altogether 5 forces, 2 at each hinge and the door's self weight. There are 2 unknown forces in the diagram since you have been told that the vertical component at each hinge is half of the door weight. 2 unknown forces and 3 equations derived from the diagram, it can be solved.
 
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