# concurrent forces

## 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 328 | Equilibrium of Force System

**Problem 328**

Two weightless bars pinned together as shown in Fig. P-328 support a load of 35 kN. Determine the forces P and F acting respectively along bars AB and AC that maintain equilibrium of pin A.

## Problem 327 | Equilibrium of Force System

**Problem 327**

Forces P and F acting along the bars shown in Fig. P-327 maintain equilibrium of pin A. Determine the values of P and F.

## Problem 319 | Equilibrium of Concurrent Force System

**Problem 319**

Cords are loop around a small spacer separating two cylinders each weighing 400 lb and pass, as shown in Fig. P-319 over a frictionless pulleys to weights of 200 lb and 400 lb . Determine the angle θ and the normal pressure N between the cylinders and the smooth horizontal surface.

## Problem 318 | Equilibrium of Concurrent Force System

**Problem 318**

Three bars, hinged at A and D and pinned at B and C as shown in Fig. P-318, form a four-link mechanism. Determine the value of P that will prevent motion.

## Problem 317 | Equilibrium of Concurrent Force System

**Problem 317**

The system of knotted cords shown in Fig. P-317 support the indicated weights. Compute the tensile force in each cord.

## Problem 316 | Equilibrium of Concurrent Force System

**Problem 316**

Determine the values of α and θ so that the forces shown in Fig. P-316 will be in equilibrium.