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
Want to see more full solutions like this?
Chapter 10 Solutions
International Edition---engineering Mechanics: Statics, 4th Edition
- The homogeneous 20-kg door is held in the horizontal plane by a thrust hinge at O, a hinge at A, and the vertical prop BC. Determine all forces acting on the door.arrow_forwardThe uniform, 20-kg bar is placed between two vertical surfaces. Assuming sufficient friction at A to support the bar, find the magnitudes of the reactions at A and B.arrow_forwardThe uniform bar of weight W is held in equilibrium by the couple C0. Find C0 in terms of W, L, and .arrow_forward
- The homogeneous bar AB weighs 25 lb. Determine the magnitudes of the forces acting on the bar at A and B. Neglect friction.arrow_forwardThe 1200-lb homogeneous block is placed on rollers and pushed up the 10 incline at constant speed. Determine the force P and the roller reactions at A and B.arrow_forwardDetermine the contact force between the smooth 90-kg ball B and the horizontal bar, and the magnitude of the pin reaction at A. Neglect the weights of the bar and the pulley.arrow_forward
- The two uniform cylinders, each of weight W, are resting against inclined surfaces. Neglecting friction, draw the free-body diagrams for each cylinder and for the two cylinders together. Count the total number of unknowns and the total number of independent equilibrium equations.arrow_forwardThe cable of mass 1.8 kg/m is attached to a rigid support at A and passes over a smooth pulley at B. If the mass M = 40 kg is attached to the free end of the cable, find the two values of H for which the cable will be in equilibrium. (Note: The smaller value of H represents stable equilibrium.)arrow_forwardThe 40-kg homogeneous disk is resting on an inclined friction surface. (a) Compute the magnitude of the horizontal force P. (b) Could the disk be in equilibrium if the inclined surface were frictionless?arrow_forward
- The 14-kN weight is suspended from a small pulley that is free to roll on the cable. The length of the cable ABC is 20 m. Determine the horizontal force P that would hold the pulley in equilibrium in the position x=5m.arrow_forwardThe 40-kghomogeneous disk is placed on a frictionless inclined surface and held in equilibrium by the horizontal force P and a couple C (C is not shown on the figure). Find P and C.arrow_forwardDetermine the ratio P/Q of the forces that are required to maintain equilibrium of the mechanism for an arbitrary angle . Neglect the weight of the mechanism.arrow_forward
- International Edition---engineering Mechanics: St...Mechanical EngineeringISBN:9781305501607Author:Andrew Pytel And Jaan KiusalaasPublisher:CENGAGE L