Conservation of Energy in Fluid Mechanics: Interactive Learning Quizzes

Question 1

Which of the following devices converts hydraulic energy into mechanical energy?

Accepted Answer

Turbine

Answer

Pump

Answer

Nozzle

Answer

Valve

Question 2

In a nozzle, the flow area decreases in the direction of flow. How does this impact the fluid's velocity?

Accepted Answer

Increases

Answer

Decreases

Answer

Remains constant

Answer

Oscillates

Question 3

Which of the following assumptions is NOT made during the derivation of the Bernoulli equation?

Accepted Answer

Compressible flow

Answer

Steady flow

Answer

Inviscid flow

Answer

Adiabatic flow

Question 4

What is the relationship between the head and power output of a turbine?

Accepted Answer

Head is proportional to power output

Answer

Head is inversely proportional to power output

Answer

Head is not related to power output

Answer

Head is equal to power output

Question 5

What is the purpose of a diffuser in a fluid system?

Accepted Answer

To decrease fluid velocity

Answer

To increase fluid pressure

Answer

To change the direction of fluid flow

Answer

To separate solid particles from the fluid

Question 6

In fluid mechanics, which term represents the change in potential energy per unit mass of the fluid?

Accepted Answer

gz

Answer

pv

Answer

V^2/2

Question 7

Which of the following is NOT considered a mechanical energy associated with fluid flow?

Accepted Answer

Electrical energy

Answer

Potential energy

Answer

Kinetic energy

Answer

Internal energy

Question 8

Consider a fluid flowing through a duct with constant cross-sectional area. If the velocity of the fluid increases, which of the following will also increase?

Accepted Answer

Kinetic energy per unit mass

Answer

Pressure

Answer

Specific enthalpy

Answer

Temperature

Question 9

The term 'head' in fluid mechanics refers to:

Accepted Answer

Potential energy per unit weight

Answer

Energy per unit mass

Answer

Kinetic energy per unit mass

Answer

Pressure per unit density

Question 10

In the differential form of the conservation of energy equation for fluid flow, which term incorporates frictional losses?

Accepted Answer

Frictional loss term

Answer

Pressure gradient term

Answer

Elevation term

Answer

Velocity term

Question 11

How primarily does a pump transfer energy to water flowing through a pipe?

Accepted Answer

Increasing velocity

Answer

Increasing elevation

Answer

Adding heat

Answer

Reducing friction

Question 12

What is a key advantage of utilizing the differential form of the conservation of energy equation over the integral form?

Accepted Answer

Provides more detailed information about energy changes along the flow path

Answer

Simplifies application to complex flow geometries

Answer

Requires fewer assumptions

Answer

More accurate for unsteady flows

Question 13

Which of the following statements aligns with the conservation of energy equation regarding velocity and pressure changes in a fluid flowing through a nozzle?

Accepted Answer

Velocity increases and pressure decreases

Answer

Velocity decreases and pressure increases

Answer

Velocity and pressure both increase

Answer

Velocity and pressure both decrease

Question 14

Which equation represents the integral form of the conservation of energy for a fluid?

Accepted Answer

∫dE = ∫δQ - ∫δW

Answer

dE = δQ - δW

Answer

dE = Q - W

Answer

δE = δQ + δW

Question 15

What is the relationship between the potential energy and pressure of a fluid in a hydrostatic system?

Accepted Answer

Pressure = potential energy

Answer

Potential energy = pressure

Answer

Potential energy < pressure

Answer

Pressure > potential energy

Question 16

Which term in the conservation of energy equation represents the energy lost due to friction in fluid flow?

Accepted Answer

hf

Answer

ρgh

Answer

P

Answer

0.5ρv²

Question 17

Which assumption is made in deriving the differential form of the conservation of energy equation?

Accepted Answer

Inviscid, incompressible flow

Answer

Viscous, incompressible flow

Answer

Inviscid, compressible flow

Answer

Viscous, compressible flow

Question 18

What is the relationship between the velocity and pressure of a fluid along a streamline in a steady, inviscid flow?

Accepted Answer

Velocity increases, pressure decreases

Answer

Velocity decreases, pressure increases

Answer

Velocity and pressure are constant

Answer

Velocity is proportional to pressure

Question 19

Which of the following is a dimensionless parameter used to characterize energy loss in turbulent fluid flow?

Accepted Answer

Friction factor

Answer

Reynolds number

Answer

Prandtl number

Answer

Nusselt number

Question 20

What is the physical significance of the stagnation pressure in fluid flow?

Accepted Answer

It is the pressure at a point where the velocity is zero

Answer

It is the pressure at a point where the acceleration is zero

Answer

It is the pressure at a point where the energy is minimum

Answer

It is the pressure at a point where the temperature is maximum

Question 21

What is the primary difference between the Bernoulli equation and the conservation of energy equation in fluid mechanics?

Accepted Answer

The Bernoulli equation ignores elevation changes

Answer

The conservation of energy equation ignores friction losses

Answer

The Bernoulli equation is valid for compressible flow, while the conservation of energy equation is not

Answer

The conservation of energy equation is valid for two-phase flow, while the Bernoulli equation is not

Question 22

A fluid flows through a pipe of varying cross-sectional area. At which point along the pipe is the pressure the **greatest**?

Accepted Answer

Point with the **smallest** cross-sectional area

Answer

Pressure is constant throughout the pipe

Answer

Point at the midpoint of the pipe

Answer

Point with the largest cross-sectional area

Question 23

A pump is used to move a fluid from a lower reservoir to a higher reservoir. Which of the following statements is true regarding the energy transfer in this process?

Accepted Answer

The pump does work on the fluid, **increasing** its potential energy

Answer

The total energy of the system remains constant

Answer

The fluid does work on the pump, increasing its kinetic energy

Question 24

Consider a turbine operating in a steady flow process. Which of the following represents the correct **differential** form of the conservation of energy equation?

Accepted Answer

-dP/ρ + V⋅dV + gdz = 0

Answer

∫(P/ρ)dA + (V²/2)dA + gz = constant

Answer

∫(V²)dA + gz + Q = constant

Question 25

A fluid enters a converging-diverging nozzle with a velocity of 10 m/s and a pressure of 100 kPa. At the throat of the nozzle, the pressure is 50 kPa. What is the velocity at the throat?

Accepted Answer

14.1 m/s

Answer

50 m/s

Answer

7.1 m/s

Question 26

A fluid flows through a pipe with a sudden enlargement. Which of the following is true regarding the pressure and velocity changes at the enlargement?

Accepted Answer

Pressure **increases**, velocity **decreases**

Answer

Pressure and velocity both increase

Answer

Pressure decreases, velocity increases

Answer

Pressure and velocity both decrease

Question 27

The efficiency of a pump is defined as the:

Accepted Answer

Ratio of **actual** power output to **ideal** power output

Answer

Ratio of ideal power input to actual power input

Answer

Ratio of actual power input to ideal power input

Answer

Ratio of ideal power output to actual power output