Concept explainers
The two homogeneous bars AB and BC are connected with a pin at B and placed between rough vertical walls. If the coefficient of static friction between each bar and the wall is 0.25, determine the largest angle 6 for which the assembly will remain at rest.
Largest angle θ for which the assembly will remain at rest
Answer to Problem 7.4P
The largest angle θ is equal to
Explanation of Solution
Given information:
Co-efficient of static friction between each bar and wall is
For impending sliding, the friction force equals its limiting value;
Steps to follow in the equilibrium analysis of a body are:
1. Draw the free body diagram.
2. Write the equilibrium equations.
3. Solve the equations for the unknowns.
Calculation:
FBD of assembly
Assume
Assume
For the equilibrium of entire section, the bending moment about point A is equal to zero.
Solve
Write equilibrium equation in vertical direction.
Write equilibrium equation in horizontal direction.
The impending sliding will first occur at point C.
The reaction force
FBD of bar BC
For the equilibrium of above section, the bending moment about point B is equal to zero.
Therefore
Conclusion:
The largest angle θ is equal to
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Chapter 7 Solutions
International Edition---engineering Mechanics: Statics, 4th Edition
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