BME Advanced Mechanics 2

Question 1

A thin-walled pressure vessel with radius r and wall thickness t is subjected to internal pressure p. What is the hoop stress?

Accepted Answer

pr/t

Answer

Hoop (circumferential) stress in a thin-walled cylinder is σ_h = pr/t, twice the longitudinal stress.

Question 2

In Euler-Bernoulli beam theory, which assumption is NOT made?

Accepted Answer

Large deflections are permitted

Answer

Euler-Bernoulli beam theory assumes small deflections; large-deflection problems require nonlinear analysis.

Question 3

Which failure criterion is most appropriate for ductile metals under multiaxial loading?

Accepted Answer

von Mises (distortion energy) criterion

Answer

The von Mises criterion accurately predicts yielding in ductile metals by considering all stress components through the distortion energy.

Question 4

A simply supported beam of length L carries a uniform distributed load w. The maximum bending moment occurs at:

Accepted Answer

x = L/2

Answer

For a uniformly loaded simply supported beam, the bending moment is parabolic and peaks at mid-span with M_max = wL²/8.

Question 5

The polar moment of inertia J for a solid circular shaft of diameter d is:

Accepted Answer

πd⁴/32

Answer

J = πd⁴/32 for a solid circle; this quantity is used in the torsion formula τ = Tr/J.

BME - Bachelor of Mechanical Engineering Practice Test