# Civil Engineering/Forces on hinges

Question

A door is 2m high, 2.5m wide and weighs 700N.The door is held in place by 2 hinges A and B. Hinge A and B are both 0.3m from the top and bottom of the door.

What are the horizontal and Vertical forces on the hinges?

Hi Harry,

This sounds like a homework question, which I should not be answering for you as you will not learn anything. Use first principles:

1. Vertical forces on hinges: hint is that overall action equals reaction and will be shared equally by the hinges.

2. Horizonatl reactions will also be equal (as they are symmetrically located) and opposite to form a couple which is equal and opposite to the applied moment by gravity moment caused by the door. (hint- take moments about vertical axis of the hinges).

Civil Engineering

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