How can equilibrium of a rigid body be determined using the given information?

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Homework Statement


[PLAIN]http://img24.imageshack.us/img24/8382/fm1u.png

Homework Equations


µ ≥ tan Θ

The Attempt at a Solution


I'm new here, if I post something wrong here. please correct me! :)
I don't understand the question.
Where is the normal reaction between the rod and the floor? from figure 1.
Is it in the same direction as the rod acting on the floor? or perpendicular to the floor?
If the normal reaction is same as the direction as the rod acting on the floor then:
Resolve vertically - R cos Θ = W
Resolve horizontally - R sin Θ + F = ?
F ≤ µR
F ≤ µW / cos Θ ? is it correct?
 
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FearOfFM said:

I don't understand the question.
Where is the normal reaction between the rod and the floor? from figure 1.
Is it in the same direction as the rod acting on the floor? or perpendicular to the floor?



The normal force is always normal to the surface. Draw the free body diagram with all forces acting on the rod. The normal force from the floor acts upward.

ehild
 
ehild said:
The normal force is always normal to the surface. Draw the free body diagram with all forces acting on the rod. The normal force from the floor acts upward.

ehild

Thanks ehild... :)
so resolve vertically R = W :)
I will try to work out this question. I will be back~!
 
FearOfFM said:
so resolve vertically R = W :)

It is not that simple. Draw all forces. There is a normal force also at the peg.The resultant torque and the resultant force both have to be zero at equilibrium.

ehild
 
Last edited:
ehild said:
It is not that simple. Draw all forces. There is a normal force also at the peg.The resultant torque and the resultant force both have to be zero at equilibrium.

ehild

I forgot there is a normal force at the peg >.<!

so R1 + R2 = W
and how to resolve horizontally?
 
The reaction force from the floor is vertical, but that of the peg is not. The forces are vectors, you have to add both the horizontal and vertical components.
What forces act horizontally?

ehild