Engineering Certification Engineering Certification Thermodynamics & Fluid Mechanics

Question 1

Which thermodynamic law states that energy cannot be created or destroyed, only converted from one form to another?

Accepted Answer

First Law

Answer

The First Law of Thermodynamics is the law of conservation of energy: the total energy of an isolated system remains constant.

Question 2

What does the Second Law of Thermodynamics state about heat transfer?

Accepted Answer

Heat flows spontaneously from hot to cold bodies

Answer

The Second Law states that heat naturally flows from a region of higher temperature to a region of lower temperature, and entropy of an isolated system increases.

Question 3

In fluid mechanics, what does Bernoulli's equation relate?

Accepted Answer

Pressure, velocity, and elevation in a flowing fluid

Answer

Bernoulli's equation states that for steady, incompressible, inviscid flow, the sum of pressure energy, kinetic energy, and potential energy remains constant along a streamline.

Question 4

What is the Reynolds number used to determine in fluid mechanics?

Accepted Answer

Whether flow is laminar or turbulent

Answer

The Reynolds number (Re = ρvD/μ) is a dimensionless ratio that predicts whether fluid flow will be laminar (Re < 2300) or turbulent (Re > 4000) in a pipe.

Question 5

Which thermodynamic process occurs at constant temperature?

Accepted Answer

Isothermal

Answer

An isothermal process occurs at constant temperature, and for an ideal gas, it follows the relationship PV = constant.

Engineering Certification Practice Test

Engineering Certification Practice Test

Engineering Certification Engineering Certification Thermodynamics & Fluid Mechanics