Need help with Static Equilibrium problem

[opqpop]

We put a 100 cm ruler on a table at the 50cm mark. The 0cm mark is on the table and the 100cm mark is in free air. The ruler is in static equilibrium.

Now we place the ruler on the table at the 40cm mark, creating a torque on the ruler so that it is not balanced.

Next attach a weightless string with some length l at some mark on the ruler.

Then put a hammer on the string so that the head of the hammer is facing toward the ground while the bottom of the hammer is touching the ruler. (The com of the hammer is towards the table)

Here is a diagram: http://img81.imageshack.us/img81/1984/abcqc5.png


Can someone tell me what all the forces acting in this system are? Thanks

 

[Shooting Star]

Please clarify certain things.

You want the weight Mg of the head of the hammer to act at some mark 'l' on the ruler, through the string which is attached at 'l'?

L = 60 cm?

The bottom of the hammer is touching the ruler at the 100 cm end?

What have you represented by force F?