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A vertical rectangular door with its cen...

A vertical rectangular door with its centre of gravity at `O` (see figure) is fixed on two hinges `A` and `B` along one vertical length side of the door. The entire weight of the door is supported by the hinge `A`. Then the free body force diagram for the door (the arrows indicate the direction of the forces) is

A

B

C

D

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The correct Answer is:
B
Because of the W of door tries to rotate it clockwise, so, to oppose this normal at hinges produces anticlockwise torque.
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