NCEES Mechanical Engineering PE Exam 2

Question 1

On the NCEES PE Mechanical exam, what does 'fatigue limit' (endurance limit) represent for a steel component?

Accepted Answer

The stress amplitude below which a material can theoretically withstand infinite load cycles without failure

Answer

The endurance limit (Se) is the stress amplitude below which a ferrous material can endure an essentially unlimited number of loading cycles without fatigue failure.

Question 2

In the NCEES PE Mechanical exam, what is the purpose of the 'Miner's rule' in fatigue analysis?

Accepted Answer

To linearly accumulate damage fractions from variable amplitude stress cycles

Answer

Miner's rule (cumulative damage theory) sums the ratios ni/Ni for each stress level, predicting fatigue failure when the sum reaches 1.0.

Question 3

For the NCEES PE Mechanical exam, which type of bearing is best suited for handling both radial and axial (thrust) loads simultaneously?

Accepted Answer

Deep-groove ball bearing

Answer

Deep-groove ball bearings can carry both radial and moderate thrust loads simultaneously due to their geometry, making them the most versatile and widely used bearing type.

Question 4

On the NCEES PE Mechanical exam, what does the AGMA bending stress equation for gear teeth primarily check?

Accepted Answer

Root bending fatigue strength of the gear tooth

Answer

The AGMA bending equation calculates the tensile bending stress at the root of the gear tooth and compares it to the material's allowable bending stress to prevent tooth breakage.

Question 5

In the NCEES PE Mechanical exam, what is 'thermal resistance' in heat transfer analysis?

Accepted Answer

An analogy to electrical resistance representing the opposition to heat flow

Answer

Thermal resistance (R = L/kA for conduction, 1/hA for convection) allows complex heat transfer problems to be solved using electrical circuit analogies.

NCEES National Council of Examiners for Engineering and Surveying Practice Practice Test

NCEES National Council of Examiners for Engineering and Surveying Practice Practice Test

NCEES Mechanical Engineering PE Exam 2