Horizontal Force on Pivot Point

[Epif]

Homework Statement

http://img151.imageshack.us/img151/6641/torquebk4.jpg

Homework Equations

T=F*r
F*X=Ia
I=ML²/3

The Attempt at a Solution

I was able to do part A easily enough, but I'm not quite sure where to even start with part B. I know that the force on the pivot point would be F₀ if X was .5L, ie the center of mass. However, I am unable to come up with the equation asked for. Thanks for any help!

 

[tiny-tim]

Hi Epif!

Hint: take moments about any point on the rod (might as well use the c.o.m.), and use "impulsive" torque = change of angular momentum.