Mechanical Aptitude Mechanical Aptitude Fluid Dynamics Principles Questions and Answers 2

Question 1

A pipe narrows from a 4-inch diameter to a 2-inch diameter. If water flows at 2 ft/s in the wider section, what is the approximate velocity in the narrower section?

Accepted Answer

8 ft/s

Answer

4 ft/s

Answer

6 ft/s

Answer

16 ft/s

Question 2

Which principle explains why a shower curtain gets pulled inward when the water is running?

Accepted Answer

Bernoulli's principle

Answer

Pascal's principle

Answer

Archimedes' principle

Answer

Boyle's law

Question 3

A hydraulic system has a small piston with an area of 5 sq in and a large piston with an area of 50 sq in. If 20 lbs of force is applied to the small piston, what force is exerted by the large piston?

Accepted Answer

200 lbs

Answer

20 lbs

Answer

100 lbs

Answer

1,000 lbs

Question 4

What happens to the flow rate in a pipe if the fluid viscosity doubles while all other factors remain constant?

Accepted Answer

Flow rate is reduced by half

Answer

Flow rate doubles

Answer

Flow rate stays the same

Answer

Flow rate is reduced to one-quarter

Question 5

A tank has two outlet holes at different heights. Which statement is correct about the water streams?

Accepted Answer

The lower hole produces a faster stream

Answer

The higher hole produces a faster stream

Answer

Both holes produce streams at the same speed

Answer

Stream speed depends only on hole size

Question 6

In a venturi meter, what happens at the narrowest section of the tube?

Accepted Answer

Pressure decreases and velocity increases

Answer

Both pressure and velocity increase

Answer

Pressure increases and velocity decreases

Answer

Both pressure and velocity decrease