Chapter 8 #26. A uniform beam of length L and mass m is inclined at an angle of
ID: 2211429 • Letter: C
Question
Chapter 8 #26. A uniform beam of length L and mass m is inclined at an angle of theta to the horizontal. Its upper end is connected to a wall by a rope, and its lower end rests on a rough horizontal surface. The coefficient of static friction between the beam and surface is ?s. Assume the angle is such that the static friction force is at its maximum value. A) Using the condition of rotational equilibrium, find an expression for the tension T in the rope in terms of m, g, and ?. B) Using Newtons second law for equilibrium, find a second expression for T in terms of ?s, m, and g. C) Using the foregoing results obtain a relationship involving only ?s and theta. D) What happens if the angle gets smaller? Is this equation valid for all values of theta? Explain. The image: http://www.webassign.net/sercp8/p8-26.gifExplanation / Answer
the rope is horizontal. how is that possible? that should be completely vertical. may the question be true! A tension will act at the left end of the beam, Weight at the center, normal reaction and friction at the right end of the beam. Equations are: A. mg(l/2) cos(theta)= Tl sin(th). B.T=F, N=mg C. mg(l/2) cos(theta)+Fl sin(th)= Nl cos(th). Where m=mass, g=accln. , l=length of beam, T=tension in the rope, F=friction, n=normal reaction. F=µs (N)