EIT Materials Science 2

Question 1

Young's modulus (modulus of elasticity) is defined as:

Accepted Answer

Stress divided by strain in the elastic region

Answer

Young's modulus E = σ/ε applies only in the linear elastic region where Hooke's Law holds.

Question 2

What is the approximate Young's modulus for structural steel?

Accepted Answer

200 GPa

Answer

Steel has a Young's modulus of approximately 200 GPa (207 GPa), a standard value used in structural engineering calculations.

Question 3

In a Brinell hardness test, hardness is determined by:

Accepted Answer

Measuring the diameter of a spherical indentation from a hardened ball

Answer

Brinell hardness (BHN) is calculated from the applied load and the area of the indentation left by a hardened steel or tungsten carbide ball.

Question 4

What does a standard Charpy impact test measure?

Accepted Answer

Energy absorbed during fracture of a notched specimen

Answer

The Charpy test measures the energy absorbed when a notched bar is struck by a swinging pendulum, assessing toughness and ductile-to-brittle transition.

Question 5

The endurance limit in fatigue testing is best described as:

Accepted Answer

The stress amplitude below which a material can theoretically endure infinite cycles

Answer

For ferrous alloys, the endurance limit is the stress amplitude below which fatigue failure will not occur regardless of the number of cycles, seen as the horizontal asymptote on an S-N curve.

(EIT) Engineer In Training Certification Practice Test

(EIT) Engineer In Training Certification Practice Test

EIT Materials Science 2