Free EIT Thermodynamics and Strength of Materials Questions and Answers

Question 1

A cantilever beam is loaded with a force of 10 KN and has a cross-section as shown. The maximum tensile stress in MPa in the beam most nearly is:

Accepted Answer

441

Answer

Explanation:
The second moment of area of the cross-section is 1.36 × 10−6𝑚𝑚4
The top of the beam is in tension.
The centroid is 50 mm up from the bottom of the cross-section.
The maximum moment is 20 KN–m.

Question 2

The maximum tensile principal stress in MPa for the two-dimensional stress state given is:

Accepted Answer

30

Answer

Explanation:
A normal compressive stress in the y-direction of 60 MPa is a negative stress.

Question 3

In all adiabatic processes, there is:

Accepted Answer

no heat flow

Answer

Explanation:
Mostly this requires the student to remember that adiabatic means (by definition) that there is no flow of heat. Then one must make sure that (B) and (C) do not also generally accompany an adiabatic process. While an adiabatic process may have no temperature change or enthalpy change, this is not generally true. For instance, enthalpy and temperature both change for an adiabatic turbine.

Question 4

A Carnot refrigerator operates between 10°𝐶𝐶 and 25°𝐶𝐶. The coefficient of performance is:

Accepted Answer

18.9

Answer

Explanation:
It's calculated using the formula for the coefficient of performance (COP) of a Carnot refrigerator.

Question 5

Air in a closed-rigid vessel at 2 bars and 25°𝐶𝐶 is heated until its temperature is 100°𝐶𝐶. The final pressure in bars is:

Accepted Answer

2.50

Answer

Explanation:
The final pressure is approximately 2.50 bars.

EIT - Engineering in Training Practice Test

EIT - Engineering in Training Practice Test

Free EIT Thermodynamics and Strength of Materials Questions and Answers