The railcar docklight is supported by the 1/8 in. diameter pin at A. If the lamp weighs 3.4 lb, and the extension arm AB has a weight of 0.45 lb/ft.
Determine the average shear stress in the pin needed to support the lamp. Hint: The shear force in the pin is caused by the couple moment required for equilibrium at A.
Express your answer to three significant figures and include appropriate units.
