Concept explainers
The couple
Answer to Problem 10.21P
The couple
Explanation of Solution
Given:
The mass of each uniform bar is
Concept used:
Apply the Principle of virtual work by providing a small angular virtual displacement of
By applying the virtual angular displacement to bar AB then bar AB will rotate, Bar BC will translate and bar CD will rotate
The virtual kinematic diagram after the angular displacement of
Write the expression to calculate linear displacement of bar AB.
Here,
Write the expression to calculate linear displacement of bar CD.
Here,
The weight force is the only force applied on the system thus, but similar triangle the displacement of center of bars AB and CD is
Write the expression for the weight of bar.
Here,
Write the expression for virtual work done on system.
Here,
Calculation:
Substitute
Displacement of bar BC will be equal to displacement of end B as there is no constraint therefore,
Substitute
Substitute
Substitute
Substitute
Substitute
The couple
Conclusion:
Thus, the couple
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Chapter 10 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