5. A 30 kg wood beam of length 3m leans on a concrete floor against a frictionless wall. What horizontal force must be supplied at the base to hold the beam in place when the angle it makes with the floor are as given below? {Present full workup starting from FBD.) a) 80" b) 45 c) 15" Use your results to explain why a ladder becomes less stable as it leans out more from a wall. 6. In problem 5: The coefficient of friction between wood and concrete is u = 0.62. Do any of the situations a. c. have a problem? Why