What you are trying to do is balance the “moments" about the fulcrum (pivot).
We will calculate moment at the pivot (M1) due to weight (W):
• L1 = length of the bar = 6in
[tex]M1=W\times L1=400\cdot6=2400in\cdot lb_f[/tex]The moment (M2) at the pivot due to your applied force (Fa) on the other end of the bar must equal M1.
• LT = total lenght = 28in
,• L2 = LT - L1 = 28 - 6 = 22in
,• M2 = M1 = 2400in lbf
[tex]\begin{gathered} M2=Fa\times L2 \\ Fa=\frac{M2}{L2}=\frac{2400inlb_f}{22in}=109.09lb_f \end{gathered}[/tex]Answer: 109.09lbf
A force of 109.091 pounds would have to be applied to move the load.
