ME or MEng Master of Engineering Structural Analysis and Materials Science 3

Question 1

The method of sections in truss analysis involves:

Accepted Answer

Cutting the truss and applying equilibrium to one portion

Answer

Solving every joint sequentially from one end

Answer

Using the stiffness matrix for all members simultaneously

Answer

Measuring deflections experimentally at each node

Question 2

Creep in materials refers to:

Accepted Answer

Slow, time-dependent plastic deformation under sustained load

Answer

Sudden brittle fracture under impact loading

Answer

Reversible elastic deformation at high strain rates

Answer

Surface corrosion under cyclic stress

Question 3

In composite materials, the rule of mixtures gives the longitudinal (fiber-direction) Young's modulus as:

Accepted Answer

E_c = E_f·V_f + E_m·V_m

Answer

E_c = E_f/V_f + E_m/V_m

Answer

E_c = (V_f/E_f + V_m/E_m)^−1

Answer

E_c = E_f·E_m/(E_f + E_m)

Question 4

Castigliano's second theorem states that the deflection at a point in a structure equals:

Accepted Answer

The partial derivative of total strain energy with respect to the applied load at that point

Answer

The second derivative of strain energy with respect to applied load

Answer

Twice the strain energy divided by the total load

Answer

The integral of moment divided by EI

Question 5

Which type of stress causes shear failure along a 45° plane in a uniaxially loaded ductile member?

Accepted Answer

Maximum shear stress

Answer

Maximum principal normal stress

Answer

Hydrostatic stress

Answer

Von Mises effective stress

Question 6

Transformation temperature A3 in the iron-carbon phase diagram represents:

Accepted Answer

The upper boundary of the two-phase (austenite + ferrite) region for hypoeutectoid steels

Answer

The eutectoid temperature (723°C) for all steel compositions

Answer

The liquidus temperature for cast iron

Answer

The martensite start temperature