## Relative Equilibrium of Liquids

Relative equilibrium of liquid is a condition where the whole mass of liquid including the vessel in which the liquid is contained, is moving at uniform accelerated motion with respect to the earth, but every particle of liquid have no relative motion between each other. There are two cases of relative equilibrium that will be discussed in this section: linear translation and rotation. Note that if a mass of liquid is moving with constant speed, the conditions are the same as static liquid in the previous sections.

## Problem 525 | Friction

Problem 525
A uniform ladder 4.8 m ft long and weighing W lb is placed with one end on the ground and the other against a vertical wall. The angle of friction at all contact surfaces is 20°. Find the minimum value of the angle θ at which the ladder can be inclined with the horizontal before slipping occurs.

## Problem 361 | Equilibrium of Non-Concurrent Force System

Problem 361
Referring to Problem 359, if T = 30 kN and x = 1 m, determine the angle θ at which the bar will be inclined to the horizontal when it is in a position of equilibrium.

## Problem 360 | Equilibrium of Non-Concurrent Force System

Problem 360
Referring to Problem 359, what value of T acting at x = 1 m from B will keep the bar horizontal. ## Problem 359 | Equilibrium of Non-Concurrent Force System

Problem 359
A 4-m bar of negligible weight rests in a horizontal position on the smooth planes shown in Fig. P-359. Compute the distance x at which load T = 10 kN should be placed from point B to keep the bar horizontal. ## Problem 351 | Equilibrium of Non-Concurrent Force System

Problem 351
The beam shown in Fig. P-351 is supported by a hinge at A and a roller on a 1 to 2 slope at B. Determine the resultant reactions at A and B. ## Problem 323 | Equilibrium of Force System

Problem 323
The truss shown in Fig. P-323 is supported by a hinge at A and a roller at B. A load of 20 kN is applied at C. Determine the reactions at A and B. ## Problem 322 | Equilibrium of Force System

Problem 322
The Fink truss shown in Fig. P-322 is supported by a roller at A and a hinge at B. The given loads are normal to the inclined member. Determine the reactions at A and B. Hint: Replace the loads by their resultant. ## Problem 315 | Equilibrium of Concurrent Force System

Problem 315
The 300-lb force and the 400-lb force shown in Fig. P-315 are to be held in equilibrium by a third force F acting at an unknown angle θ with the horizontal. Determine the values of F and θ. 