Answer:
Length of beam = 10in
Explanation:
We first calculate the maximum shear force.
[tex]Max shear force =\frac{V*A*y'}{Ib}[/tex]
[tex] 1200=\frac{V(2*1)0.5}{\frac{2*2^3}{12}*2}[/tex]
Calculating for V, we have:
V = 3200Ib
P = 3200 *2
P = 6.4k
Let's now use the equation for the load for a length.
[tex]M =\frac{PL}{4}[/tex]
[tex] M =\frac{6.4*L}{4}[/tex]
Using the stress equation,
[tex]\frac{M}{I}=\frac{o}{y}[/tex]
Inputting figures in the equation, we have:
[tex]\frac{6400*L}{4*\frac{2*2^3}{12}}=\frac{12000}{1}[/tex]
Solving for L, we have:
L = 10in
Length of beam will = 10in