Exercise $3$

The forearm and biceps support a load at point $\backslash ($ A $\backslash )$ as shown in Figure $3.\backslash ($ C $\backslash )$ can be assumed as a pin support. The biceps pulls on the bone along $\backslash ($ B D $\backslash ).$

$($a$)$ Determine the resultant internal loadings acting on the cross section of the bone of the forearm at point $\backslash ($ F $\backslash )$ for

$($i$)$ A mass of $\backslash ($ m$=2\backslash$mathrm$\{$~kg$\}\backslash )$ at $\backslash ($ A $\backslash )$

$($ii$)$ A mass of $\backslash ($ m$=6\backslash$mathrm$\{$~kg$\}\backslash )$ at $\backslash ($ A $\backslash )$

$($b$)$ Assuming the same geometry is maintained, what mass $\backslash ($ m $\backslash$mathrm$\{$~kg$\}\backslash )$ at point $\backslash ($ A $\backslash )$ would cause the force in the bicep to reach $650$ N $($close to maximum limit for average bicep muscle$)?$