Q$2$:

For the system given in the figure, if the load is acting at point $B$;

a$)$ Check the safety of the bars $BC$ and $AB.$ Note that the cross sections of the bars are identical.

b$)$ Calculate change in lengths of $BC$ and $AB$ bars $?,L_{AB}=?)$ and determine the displacement of point $B.$

c$)$ Based on the connection detail at point C $($Detail C and section $1-1),$ determine appropriate pin diameter to transfer the shear force safely.

For the bars:

${}_{\text{a}\text{l}\text{l}}=14k\frac{N}{c}{m}^2,E=21000k\frac{N}{c}{m}^2$

For the pin:

${}_{\text{a}\text{l}\text{l}}=14k\frac{N}{c}{m}^2$