What are the reactions at the base of the light pole in fig.1?

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SUMMARY

The discussion focuses on determining the reactions at the base of a light pole subjected to a downward force of 185g N and a clockwise moment of 125g N. It is established that the reaction force at the base must balance both the vertical force and the moment, requiring two forces or a combination of a force and a moment for equilibrium. The participants emphasize the need for understanding how the reaction force contributes to counteracting the clockwise moment while also addressing horizontal components.

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Homework Statement


Determine the reactions at the base of the light pole shown in fig.1


Homework Equations


Summation of force and moment of a system in equilibrium is 0.


The Attempt at a Solution


The resultant force of due to the weight of the light pole and lamp is 185g N, vertically downward without horizontal component. The moment at the base of the light pole caused by the weight is 125g N, clockwise direction.

I realize that a reaction force at the base is needed to balance the moment, hence the reaction force will not be perpendicular to the ground. However, if that is not the case, how do you balance the horizontal component of the reaction force?

Also, if we take moment at the base, how can the reaction force contribute to the anticlockwise moment needed to counter the clockwise moment contributed by the weight?

Thanks in advanced. :)
 

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Hi...
The problem is that the reaction for an extended body is not equivalen to a sigle force.
You need 2 forces or a force and a moment.

http://dc60.2shared.com/img/3767972/bb0c147f/forces.bmp
 
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