Well that's my main problem, maybe lack of information in the problem. I'm not sure with my solution. All of my classmates didn't get the right answer as what my teacher said. Maybe my teacher forgot to write some details in the drawing. Am i right?
Seatwork no. 1 -------Strength of Materials----------
The 20 mm diameter bolt fastens two wooden planks together. The nut is tightened until the tensile stress in the bolt is 150 Mpa. Find the smallest safe diameter “d” of the washers, if the working bearing stress for wood is 13 Mpa...