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The brake pads at C and D are pressed against the cylinder by the spring BF. The coefficient of static friction between each pad and the cylinder is 0.15. Find the smallest tension in the spring that would prevent the cylinder from rotating when the clockwise couple
Smallest tension in the spring
Answer to Problem 7.8P
The smallest tension
Explanation of Solution
Given information:
The co-efficient of static friction between pad and cylinder is 0.15.
Couple M is equal to
If there is no relative motion between two surfaces that are in contact, The relationship between normal force
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 EF
Assume
Assume
For the equilibrium of above section, the bending moment about point E is equal to zero.
FBD of AB
Assume
Assume
For the equilibrium of above section, the bending moment about point A is equal to zero.
FBD of the cylinder
For the equilibrium of above section, the bending moment about point O is equal to zero.
Substitute and solve
Conclusion:
The smallest tension
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Chapter 7 Solutions
International Edition---engineering Mechanics: Statics, 4th Edition
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- International Edition---engineering Mechanics: St...Mechanical EngineeringISBN:9781305501607Author:Andrew Pytel And Jaan KiusalaasPublisher:CENGAGE L