6 Minor energy losses in pipe flow a Are minor and can alway

6. Minor energy losses in pipe flow: a) Are minor and can always be neglected b) Are significant when the pipe is straight and long c) Are significant when the pipe is short and has bends d) Are determined from the Moody diagram e) None of the above 7. Valid expressions of the conservation of mass for pipe flow are: c) At a Junction 0-0 d) As pressure head decreases, Q increases c) None of the above 8. Types of energy in pipe flow are a) Kinetic V12g b) Potential h c) Reynolds Re d) Pressure p/pg e) None of the above Whether pipe flow is laminar or turbulent is entirely determined by: a) side wall shear stress b) Reynolds number c) Darcy friction factor f d) relative roughness &/D e) None of the above 9. Flow in a hydraulically smooth pipe always: a) has zero shear stres b) has zero minor losses c) has zero roughness d) is laminar e) is turbulent 10. None of the above

Solution

6) Option C is correct. If pipe is short and have bends then minor lossses are significant.

7) Option A is correct. For conservation of mass discharge is constant.

8) A and D are correct. Kinetic energy and pressure energy are there in pipe flow.

9) Option B is correct . It is determined by reynolds number.

10) Option C is correct. It has zero roughness.