Engr 312 Test 1

in mohr's circle, the center of circle from Y-axis is taken as

(SigX + SigY)/2

the maximum deflection of a fixed beam of length L carrying a central point load W is

(WL^3)/192EI

when a circular bar tapering uniformly from diameter d1, at one end to diameter d2 at the other end, is subjected to an increase in temp. t, then the thermal stress induced is ________ (where a = coefficient of linear expansion, E = modulus of elasticity for bar material

(atEd1)/d2

strain is equal to ( where L= original length, and del_L = change in length

(del_L)/L

when a bar of length L and diameter D is rigidly fixed at the upper end and hanging freely, then the total elongation produced in the bar due to its own weight is (where w = weight per unit volume of the bar)

(wl^2)/2E

A bar of length L meters extends by "I" mm under a tensile force of P. The strain produced in the bar is ______

.001 I/L

when a body is subjected to bi-axial stress i.e. direct stresses SigX and SigY in two mutually perpendicular planes accompanied by a simple shear stress Txy then maximum shear stress is

.5 * sqrt((SigX - SigY)^2 + 4Txy^2)

in order to avoid sliding of masonry dam, the force of friction between there dam and soil should be at least ______ the total water pressure per meter length

1.5 times

According to Euler's column theory, the crippling load of a column is given by p = n^2 EI/CI^2. In the Euler's formula, the value of C for a column with one end fixed and the other end free, is

4

a body is subjected to a tensile stress of 1200 Mpa on one plane and another tensile stress of 600 Mpa on a plane at right angles to the former. it is also subjected to a shear stress of 400 Mpa on the same planes. the minimum normal stresses will be

400 Mpa

two bars of different materials and same size are subjected to same tensile force. if the bars have unit elongation in the ratio of 2:5, then the ratio of modulus of elasticity of the two materials will be

5:2

the given figure shows the Mohrs circle of stress for two unequal and like principle stresses (SigX and SigY) acting at a body across two mutually perpendicular planes. the resultant stress is given by

OP

if the modulus of elasticity of a material is twice its modulus of rigidity, then the poisson's ratio of the material is equal to zero

correct

modulus of resilience is the proof resilience per unit volume of a material

correct

the pull required to crush the rivet per pitch length is

d*t*SigC

in a beam subjected to pure bending, the intensity of stress in any fibre is ____ the distance of the fibre from the neutral axis

directly proportional to

when a beam is subjected to a bending moment, the strain in a layer is _______ the distance from the neutral axis.

directly proportional to

a simply supported beam A of length L, breadth b and depth D carries a central load W. Another beam 'B' of the same dimensions carries a central load equal to 2W. The deflection of beam B will be _______ as that of beam A

double

when one plate overlaps the other and the two plates are riveted together with two rows of rivets, the joint is known as

double riveted lap joint

flexibility

f = 1/K

when there is no increase or decrease in shear force between two points, it indicates that there is no change in the bending moment between these points.

false

the design of thin cylindrical shells is based on

hoop stress

When a bar of length L, width B and thickness T is subjected to a pull of P, its _________

length increases, width and thickness decreases

the breaking stress is _______ the ultimate stress

less than

the deformation of the bar unit length in the direction of the force is known as _____

linear strain

the polar moment of inertia of a solid circular shaft of diameter D is

nD^4/32

a beam of T-section is subjected to a shear force of F. the maximum shear force will occur at the

neutral axis of the section

in watches, the spring is used to absorb shocks and vibrations

no

A column with maximum equivalent length has ________

one end fixed and the other end free

When a body is subjected to a direct tensile stress in one plane, the maximum shear stress is ______ the maximum normal stress

one-half

the shear force diagram for a cantilever beam of length L and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is a

parabolic curve

the total strain energy stored in a body is termed as

resilience

Hooke's law

sigma = Ee

which of the following statements is correct?

stress is directly proportional to strain within elastic limit

The unit of modulus of elasticity is the same as those of ________

stress, pressure, and modulus of rigidity

the springs in breaks and clutches are used to

to apply forces

The product of tangential force acting on the shaft and its distance from the axis of the shaft (i.e. radius of shaft) is known as________

twisting moment

the ratio of the largest load in a test to the original cross-sectional area of the test piece is called

ultimate stress

Poisson's ratio

v = - lateral strain/axial strain

A rod is enclosed centrally in a tube and the assembly is tightened by rigid washers. If the assembly is subjected to a compressive load, then ________

Both the rod and tube are under compression

the relationship between young's modulus E, shear modulus C, and bulk modulus K is given by

E = (9KC)/(3K +C)

Stiffness

K = force/deflection

A column of length L with both ends fixed may be considered as equivalent to a column of length _______ with both ends hinged

L/2

A shaft revolving at w rad/s transmits torque T in N-m. The power developed is _____

T.w watts

The shear force and bending moment are zero at the free end of a cantilever beam, if it carries a ______

Uniformly distributed load over the whole length

which of the following statements is correct?

a uniformly distributed load spreads uniformly over the whole length of a beam

parallel fillet welds are designed for bending strength

agree

the thermal of temperature stress is a function of

all of these: - increase in temp. - modulus of elasticity - coefficient of linear expansion

a beam of uniform strength may be obtained by

any one of the above: -keeping the width uniform and varying the depth -keeping the depth uniform and varying the width -varying both the width and depth

which of the following statements is wrong?

at the neutral axis of a beam, the bending stress is maximum

a bolt is made to pass through a tube and both of them are tightly fitted with the help of washers and nuts. if the nut is tightened, then

bolt is under tension and tube is under compression

the maximum deflection of a fixed beam carrying a central point load lies at

center of beam

the volumetric strain is the ratio of the

change in volume to original volume