1. The problem statement, all variables and given/known data A uniform pine beam, 3.6 m long and 9.5 cm x 14 cm in cross section, rests on two supports near its ends, as shown. The beam’s mass is 25 kg and two vertical roof supports rest on it, each one-third of the way from the ends. What maximum load force FL can each of the roof supports exert without shearing the pine beam at its supports? Use a safety factor of 5.0. 2. Relevant equations 3. The attempt at a solution Answer sheet: F= 1/5 x A x Maximum stress I just don't understand the first step. Why did I multiply it by 1/5??? And what does safety factor mean?