Mechanics of Materials I

Chapters 1-3

when a ____ shaft is subjected to torsion, every cross section remains the same (plane and undistorted)

circular

true strain is ____ engineering strain

less than

True stress is engineering stress

greater than

Brittle materials fail

suddenly

k=(E)/(3(1-2v)) the elastic constant is known as the _

Bulk modulus

loading is considered to be ____ when the line of action of the load does not pass through the centroid of the cross section

eccentric

properties of ____ are dependent of direction testing

anisotropic

"permanent set" occurs when a material is loaded _

past its yield point

the stress concentration factor k is developed assuming a ____ relationship between stress and strain

linear

Poisson's ratio is defined as

-lateral strain/axial strain

_ is defined as the change in volume per unit volume

dilation

properties of _ materials are independent of direction

isotropic

The shear modulus, G is also known as the

modulus of rigidity

in the _ regime, stress is linearly related to strain

elastic

except in the immediate vicinity of the point of application of the load, the distribution of normal stress is an axially loaded member assumed to be _

uniform

___ problems are those in which the reactions and internal forces cannot be determined from statics alone

statically indeterminate

shearing strain in a circular shaft under torsion is ____ at the axis of the shaft

zero

When a circular shaft is subject to torsion, every cross-section remains

plane

Increasing the radius of a fillet in a flat bar under axial loading ___ the stress concentration factor

decreases

All ductile materials have well defined yield points

false

The factor of safety is defined by the equation

FS = Ultimate Load/Allowable Load

the modulus of elasticity of a material is also known as

Young's modulus

The coefficient of thermal expansion has units of

per degree C

1 hp is equal to

6600 in.lb/s

_ materials are characterized by their ability to yield at normal temperatures

ductile

the constant k as related to the application of hydrostatic pressure is known as the ___

bulk modulus

The Bulk modulus is also known as the___

modulus of compression

the ratio of the maximum value of the stress occurring near a discontinuity over the average stress determined in the critical section is referred to as the _

stress concentration factor

_ describes the resistance of a cross-section to Torsion due to its shape

polar moment of inertia

ductile materials loaded in axial tension fail

after significant deformation