Mechanical Aptitude Fluid Dynamics Principles Questions and Answers 2

Question 1

According to Bernoulli's principle, what happens to the pressure of a fluid as its velocity increases?

Accepted Answer

Pressure decreases

Answer

Bernoulli's principle states that an increase in fluid velocity corresponds to a decrease in pressure. This is because the total energy (kinetic + potential + pressure) along a streamline remains constant.

Question 2

What does viscosity measure in a fluid?

Accepted Answer

Resistance to flow

Answer

Viscosity is a measure of a fluid's resistance to flow or deformation. High-viscosity fluids like honey flow slowly, while low-viscosity fluids like water flow easily.

Question 3

What type of flow is characterized by smooth, parallel layers of fluid with no mixing between them?

Accepted Answer

Laminar flow

Answer

Laminar flow consists of smooth, orderly layers of fluid moving in parallel without mixing. It occurs at low velocities and in fluids with high viscosity. Turbulent flow, by contrast, involves chaotic mixing and eddies.

Question 4

What principle explains why a heavier-than-water steel ship floats?

Accepted Answer

Archimedes' principle

Answer

Archimedes' principle states that a body submerged in fluid experiences an upward buoyant force equal to the weight of fluid it displaces. A steel ship floats because its hull shape displaces enough water to create a buoyant force exceeding the ship's weight.

Question 5

In a venturi tube, where is the fluid velocity the highest?

Accepted Answer

At the narrowest section (throat)

Answer

The continuity equation (A₁V₁ = A₂V₂) requires that fluid velocity increases as the cross-sectional area decreases. In a venturi tube, the throat (narrowest section) has the highest velocity and lowest pressure.

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Test Practice Test

Mechanical Aptitude Fluid Dynamics Principles Questions and Answers 2