MS MS in Mechanical Engineering 1 — Questions and Answers
Question 1: What is the first law of thermodynamics also known as?
- Law of conservation of energy (Correct answer)
- Law of entropy increase
- Newton's second law
- The ideal gas law
Correct answer: Law of conservation of energy
The first law of thermodynamics states that energy cannot be created or destroyed, only converted from one form to another — it is the law of energy conservation.
Question 2: Which dimensionless number in fluid mechanics represents the ratio of inertial forces to viscous forces?
- Reynolds number (Correct answer)
- Mach number
- Prandtl number
- Nusselt number
Correct answer: Reynolds number
The Reynolds number (Re = ρvL/μ) predicts whether flow will be laminar or turbulent by comparing inertial to viscous forces in a fluid.
Question 3: What does FEA stand for in mechanical engineering analysis?
- Finite Element Analysis (Correct answer)
- Fluid Energy Assessment
- Fatigue Engineering Algorithm
- Force Equilibrium Analysis
Correct answer: Finite Element Analysis
Finite Element Analysis (FEA) is a numerical method that divides a structure into small elements to simulate stress, strain, heat transfer, and other physical behaviors under load.
Question 4: Which type of stress results when equal and opposite forces act parallel to a cross-sectional surface?
- Shear stress (Correct answer)
- Tensile stress
- Compressive stress
- Bending stress
Correct answer: Shear stress
Shear stress (τ = F/A) occurs when forces act parallel to the cross-sectional area, causing adjacent material planes to slide relative to each other.
Question 5: What is the purpose of a heat exchanger in engineering systems?
- To transfer thermal energy between two fluid streams without mixing them (Correct answer)
- To convert heat directly into mechanical work
- To store thermal energy for later use
- To measure temperature differentials in fluids
Correct answer: To transfer thermal energy between two fluid streams without mixing them
Heat exchangers facilitate thermal energy transfer between two fluids at different temperatures through a separating wall, without the fluids mixing.
Question 6: Which manufacturing process uses a mold and pressure to shape molten metal into a desired form?
- Die casting (Correct answer)
- Extrusion
- Forging
- Sintering
Correct answer: Die casting
Die casting forces molten metal under high pressure into a precision mold (die), producing complex shapes with tight tolerances and smooth surface finishes.
MS MS in Mechanical Engineering 1
What is the first law of thermodynamics also known as?