4. If the distributed load follows a normal distribution f ~ N(60, 2²) lb/ft, determine the distributions of the internal normal force and shear force acting at point B of the two-member frame shown in the figure.

Solution

A free-body diagram is shown below.

Due to , we know .

Thus, .

Solving the equations, we have and .

From the free-body diagram below,

Thus, the normal force is ；the shear force is . Ans.