Mechanical Aptitude Fluid Dynamics Principles Questions and Answers

Question 1

An incompressible fluid flows through a horizontal pipe that narrows to half its original diameter.
What happens to the fluid's velocity and pressure in the narrow section compared to the wider section?

Accepted Answer

Velocity increases and pressure decreases.

Answer

Velocity decreases and pressure increases.

Answer

Both velocity and pressure increase.

Answer

Both velocity and pressure decrease.

Question 2

A hydraulic lift is used to raise a 2,000 kg car. The piston supporting the car has a surface area of 2.5 m², and the input piston where force is applied has a surface area of 0.1 m². What is the minimum force that must be applied to the input piston to lift the car? (Assume g = 10 m/s²)

Accepted Answer

800 N

Answer

1,250 N

Answer

20,000 N

Answer

50,000 N

Question 3

Which of the following principles primarily explains why a large steel ship floats on water, while a small steel ball sinks?

Accepted Answer

Archimedes' Principle

Answer

Pascal's Law

Answer

Bernoulli's Principle

Answer

The Continuity Equation

Question 4

Viscosity is a measure of a fluid's:

Accepted Answer

Resistance to flow

Answer

Density

Answer

Compressibility

Answer

Surface tension

Question 5

A river flows from a wide channel into a narrow gorge. According to the principle of continuity, what must happen to the speed of the water as it enters the gorge?

Accepted Answer

It increases

Answer

It decreases

Answer

It remains constant

Answer

It becomes turbulent

Question 6

In a hydraulic system, if a force of 50 N is applied to a small piston with an area of 0.02 m², what is the pressure transmitted throughout the fluid?

Accepted Answer

2,500 Pa

Answer

1,000 Pa

Answer

1 Pa

Answer

50 Pa

An incompressible fluid flows through a horizontal pipe that narrows to half its original diameter.What happens to the fluid's velocity and pressure in the narrow section compared to the wider section?

An incompressible fluid flows through a horizontal pipe that narrows to half its original diameter.
What happens to the fluid's velocity and pressure in the narrow section compared to the wider section?