Chapter 3, Problem 4P

Assuming that P=48000lb and that it may be applied at any joint on the line FJ, determine the location of P that would cause (a) maximum tension in member HI; (b) maximum compression in member CI; and (c) maximum tension in member CI. Also determine the magnitude of the indicated force in each case.

The 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.

Determine 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.

Neglecting friction, determine the relationship between P and Q, assuming that the mechanism is in equilibrium in the position shown.

The cable is loaded by an 80-lb vertical force at C and a horizonal force P at B. Determine P.

(a) Find the forces in members CE, CF, and DF. (b) Identify all the zero -force members.

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.

The 60-lb homogeneous door is supported by hinges at A and B, with only the hinge at B being capable of providing axial thrust. The cable CD prevents the door from fully opening when it is pulled by the 40-lb force acting perpendicular to the door. Draw the FBD for the door, and count the unknowns.

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.