# Flow of Hydraulic Fluids - MCQs and Answers

## Flow of Hydraulic Fluids – MCQs and Answers

1. How is laminar flow characterized in a straight pipe?

a. flow of high shear stress
b. flow of high velocity
c. flow of low-velocity
d. none of the above

2. What is the characteristic of turbulent flow?

a. high velocity
b. the direction of flow and movement of particles is same
c. change in cross section does not affect the flow
d. all the above

3. Which flow pattern gets affected when cross section of the pipe is changed?

a. laminar flow
b. turbulent flow
c. laminar and turbulent
d. none of the above

4. Which of the following statements is/are true according to Bernoulli's principle?

1. If a system has constant flow rate, change in cross-section area of the pipe affects the total energy of system
2. The change in cross-section has no effect on the total energy of the system and is constant if it has varying flow rate
3. A system has constant total energy, if flow rate is constant and change in cross-section has no effect on total energy

a. Statement 1
b. Statement 2
c. Statement 3
d. All of the above

5. Speed of the actuator is affected by

a. cross-section area of the orifice
b. velocity of flow
c. pipe diameter
d. all the above

6. Why according to Bernoulli's principle, change in cross-section area of the pipe has no effect on total energy of the system?

a. when area of pipe increases upstream, kinetic energy of fluid decreases as velocity of fluid increases and potential energy increases

b. when area of pipe increases upstream, kinetic energy of fluid decreases as velocity of fluid decreases and potential energy increases

c. when area of pipe increases upstream, kinetic energy of the fluid increases as velocity of fluid decreases and potential energy decreases

d. when area of pipe increases upstream, kinetic energy of fluid increases as velocity of fluid increases and potential energy decreases

ANSWER: b. when area of pipe increases upstream, kinetic energy of fluid decreases as velocity of fluid decreases and potential energy increases

7. In which of these applications Bernoulli's principle is widely used?

a. design of blowers
b. design of aircraft wings
c. design of propellers
d. all the above

8. The total energy developed by the hydraulic oil in a system is given as

a. Total energy = ( Potential energy + Pressure energy)
b. Total energy = ( Potential energy + Kinetic energy)
c. Total energy = ( Potential energy – Kinetic energy)
d. None of the above

ANSWER: b. Total energy = ( Potential energy + Kinetic energy)

9. If a pump gives higher flow rate to the valve then, pressure drop in the valve

a. increases
b. decreases
c. remains the same
d. none of the above

10. Match the following Group-1 with Group-2 and select the correct answer from the options below

(A) pressure head -------------------------- (1) μ / ρ

(B) velocity head ---------------------------- (2) vd / ν

(C) kinematic viscosity --------------------- (3) v2 /ρg

(D) Reynolds number ----------------------- (4) p / ρg

-----------------------------------------------------(5) v2 / 2 g

a. A-(5), B-(3), C-(2), D-(1)
b. A-(4), B-(1), C-(3), D-(2)
c. A-(4), B-(5), C-(1), D-(2)
d. A-(3), B-(5), C-(2), D-(1)