# Equilibrium and Elasticity

## EXERCISES & PROBLEMS

EXERCISES & PROBLEMS ssm Solution is in the Student Solutions Manual. www Solution is available on the World Wide Web at: http://www.wiley.com/col\ege/hrw Ilw Solution is available on the Interactive LeamingWare. Some Examples 01 Static Equilibrium IE. A physics Brady Bunch, whose weights in newtons are indicated , is balanced on a seesaw. What is the number of the …

## Hydraulic Stress

Hydraulic Stress The stress is the fluid pressure p on the object, which, as you will see in Chapter 15, is a force per unit area. The strain is , where V is the original volume of the specimen and is the absolute value of the change in volume. The corresponding modulus, with symbol B, is called the …

## Shearing

Shearing In the case of shearing, the stress is also a force per unit area, but the force vector lies in the plane of the area rather than perpendicular to it. The strain is the dimensionless ratio , with the quantities defined.

## Tension and Compression

Tension and Compression For simple tension or compression, the stress on an object is defined as , where F is the magnitude of the force applied perpendicularly to the area A on the object. The strain, or unit deformation, is then the dimensionless quantity , the fractional (or sometimes percentage) change in the length of the specimen. If …

## Elasticity

Elasticity When a large number of atoms come together to form a metallic solid, such as an iron nail, they settle  equilibrium Positions in a three-dimensional lattice. a repetitive arrangement in which each atom has a well-defined equilibrium distance from its nearest neighbors. The atoms are held together by inter atomic forces that are modeled as tiny springs. If …

## Indeterminate Structures

Indeterminate Structures For the problems of this chapter, we have only three independent equations at our disposal, usually two balance of forces equations and one balance of torques equation about a given rotation axis. We have all had experience with a wobbly restaurant table, which we usually level by putting folded paper under one of the legs. If …

## PROBLEM SOLVING TACTICS

PROBLEM SOLVING TACTIC Here is a list of steps for solving static equilibrium problems: 1. Draw a sketch of the problem. 2. Select the system to which you will apply the laws of equilibrium. drawing a closed curve around it on your sketch to fix it clearly in your mind. 3. Draw e free-body diagram of the …

## Sample Problem

Sample Problem Shows a safe. of mass M = 430 kg. hanging by a rope from a boom with dimensions a = 1.9 m and b = 2.5 m. The boom consists of a hinged beam and a horizontal cable that connects the beam to a wall. (a) What is the tension in the cable? In other words, …

## Sample Problem

Sample Problem A ladder of length L = 12 m and mass m = 45 kg leans against a slick (friction less) wall. Its upper end is at height h = 9.3 m above the pavement on which the lower end rests (the pavement is not friction less). The ladder’s center of mass is L/3 from the lower end. A …

## Sample Problem

Sample Problem A uniform beam, of length L and mass 11/ = 1.8 kg. is at rest with its ends on two scales. A uniform block. with mass M = ~.7 kg. is at rest on the beam. with its center a distance , from the beam’s left end, What do the scales read? SOLUTION :The first steps in …