There are two formulas that I have encountered so far for shear stress in my Engineering class.
- Let S be shear stress, F be force, and A be cross sectional area:
S = F/A
- Note: This formula is for circular cross sections. Let S be shear stress, T be torque, C be max radius (for maximum shear stress), and J be polar moment of inertia
S = TC/J
When do I use which formula? So far 1. has been used when dealing with forces perpendicular to longitudinal axis and 2. has been used when a twisting force is applied (torque). However, I am doing a question and am stumped because they using 1. to calculate max torque of bolts in a flange. As shown below:
Why don't they use S = TC/J like every other problem in this chapter???