The connection at point A, which is shown in a magnifi ed
cross-sectional view, supports a 4.1-kN force.
8 in diameter bolt connects the marine propeller to a boat’s 1 in. driveshaft .To protect the engine and transmission if the propeller accidentally strikes an underwater obstacle, the bolt is designed
to be cut when the shear stress acting on it reaches 25 ksi. Determine the
contact force between the blade and obstacle that will cause the bolt to be
sheared, assuming a 4-in. effective radius between the point of contact on the blade and the center of the driveshaft.
picture ( http://img687.imageshack.us/img687/1124/captureboc.png )